Highlights
T. Stieler
90'
+ 6
Union up and running with Behrens hat-trick
The hosts made an electric start, going 2-0 up inside the opening ten minutes with a couple of Behrens headers, the first of which was the quickest Union scored at the Stadion An der Alten Försterei in the Bundesliga. Although they struggled for large parts, Mainz were back in it thanks to Anthony Caci's tasty volley. Incredibly, Frederik Rönnow would deny the out-of-form Ludovic Ajorque twice from the penalty spot. That this was Union's day was rarely in doubt, however, and Urs Fischer's men hammered home their advantage when Behrens completed his hat-trick before Milos Pantovic rounded off the scoring.
90'
+ 6
Full time
The referee brings this highly-entertaining contest to an end. Hats off to Union, who start the season with a bang.
90'
+ 6
Union home free
The hosts hit Mainz with a deadly breakaway goal. Kevin Volland gets the ball on the right and then plays an expert pass in for the onrushing Pantovic, who finishes in style.
Full-time
Goal probability 
Goal probability
Goal probability determines the likelihood that the ball will land in the goal from every position on the pitch. The value is based on large amounts of data from previous years; factors such as shot angle, distance to goal and opponent pressure - as well as mathematical models.
90'
+ 3
Van den Berg booked
Van den Berg cuts down Milos Pantovic and that's a yellow card for the Mainz defender.
90'
Welcome back Kevin Volland!
The striker is back in the Bundesliga! Union throw the former Bayer Leverkusen man into the mix for the closing stages. Huge ovation for hat-trick hero Behrens.
90'
Speed check: The fastest player in the game after 90 minutes
Speed check: The fastest player in the game after 90 minutes
Through high-end camera technology and machine learning, the speed of each player is evaluated in real time. Top speed then means, the fastest measured single frame of a player/game.
89'
Rönnow saves ... AGAIN !
Unbelievable. Ajorque has had a second penalty saved by Rönnow, who gets down low to stop another spot kick in this crazy game.
89'
Penalty Mainz!
The referee is asked to have a look at an incident involving Ajorque inside the area and subsequently decides to award Mainz a penalty. It's their second spot-kick of the game.
89'
Substitution
89'
Substitution
86'
Rönnow nerves
Union's goalkeeper flaps at a cross and is lucky that Caci's follow up is blocked.
86'
SituationPenalty
ReviewHandball?
DecisionPenalty
85'
Mainz possession increase
Possession (%)
5050
82'
Mainz change things up
Krauß and Weiper are now on for Mainz as they go in search of a second goal here. Still time for Bo Svensson's men to rescue something here, although this has rarely looked like being anything other than Union's day.
81'
Substitution
81'
Substitution
The Kevin Behrens show
© Getty
76'
Changes
Aymen Barkok makes his way on for Mainz while Milos Pantovic is on for Brenden Aaronson for Union.
76'
Substitution
75'
Substitution
74'
Mainz hit the woodwork
Da Costa, on the right, whips one into the mixer. Ajorque leaps and powers a header against the upright. The big man falls and stares into the sky. It just hasn't been his day.
71'
Behrens treble
Behrens scores it! Of course he does. And of course it's a header, a third. Becker holds the ball up brilliantly before edging his way out to the right. A deadly cross follows and that man Behrens is there again to head in and complete his first-ever Bundesliga hat-trick. Scenes.
Goal probability
Goal probability
Goal probability determines the likelihood that the ball will land in the goal from every position on the pitch. The value is based on large amounts of data from previous years; factors such as shot angle, distance to goal and opponent pressure - as well as mathematical models.
68'
Shots aplenty
Goal attempts
5off target
5on target
5off target
2on target
67'
Double swap
Here comes Robin Gosens to make his Bundesliga debut for Union. Sheraldo Becker is also on for the hosts.
66'
Substitution
66'
Substitution
65'
Mainz back in it
Awesome goal from the visitors. Da Costa's cross is nodded clear by Trimmel but the ball drops perfectly for Anthony Caci, who shapes himself before thumping a volley into the far corner. Cracking strike.
Goal probability
Goal probability
Goal probability determines the likelihood that the ball will land in the goal from every position on the pitch. The value is based on large amounts of data from previous years; factors such as shot angle, distance to goal and opponent pressure - as well as mathematical models.
63'
Ajorque misses pen.
Frederik Rönnow gets down to save the penalty and the stadium erupts. Union maintain their 2-0 lead.
61'
Penalty Mainz!
Amazing! Gruda is only on and he's won Mainz a penalty. Digo Leite goes in a little too heavily on the Mainz sub and the spot kick is awarded.
60'
Double swap
Gruda and Van den Berg come on for Mainz, the latter for the first time in the Bundesliga for the 05ers.
60'
Substitution
60'
Substitution
59'
Fofana off target
Fofana wafts the free kick over the top.
58'
Da Costa booking
Da Costa downs Kral on the edge of the Mainz area and that's going to be a free kick in an interesting position for Union. Yellow card for Da Costa.
53'
Behrens again
Behrens rises highest to meet the corner and his header darts not too far wide of the upright.
51'
Kohr booked
Kohr trips Behrens and goes into the referee's notebook.
48'
Ajorque struggling
The visitors are playing with more urgency and although their efforts to get the ball to Ludovic Ajorque have been successful, the big forward is having trouble in possession. Ajorque does not look comfortable out there.
46'
Off we go again
Mainz - who are up against it here - get the second half underway.
Kick-off!
45'
+ 6
Half time
Union are on fire. Mainz, not so much. A quick-fire Behrens double has last season's fourth-placed Bundesliga finishers cruising here. The 05ers are certain to face a Bo Svensson tongue lashing at the break.
Half-time
45'
+ 4
Diogo Leite goes close
Mainz look to clear their lines but the defensive header drops straight to Diogo Leite. The Portuguese dinks one up towards the top corner and this looks in, until Zentner dives up and palms brilliantly over the bar. Super save.
Behrens knock
© Getty
40'
Mainz's tough task
Not good news for the visitors. Union haven't lost in their last 58 Bundesliga games when in front (42 wins, 16 draws).
37'
Shots
4
1
David Datro Fofana Danny da Costa
32'
Union hit the bar
From the resulting free kick, Fofana pelts a delicious free kick off the crossbar. What a strike that was. Union fans with heads in hands.
31'
Lee booking
Lee hacks Behrens to the floor and the referee has an easy decision to make. Yellow card for the Mainz man.
30'
05ers seeking
Better from Mainz, who finally work the ball into the Union area. Barreiro's effort is blocked. Soon afterwards, Da Costa wellies over the top.
30'
Speed check: The fastest player in the game after 30 minutes
Speed check: The fastest player in the game after 30 minutes
Through high-end camera technology and machine learning, the speed of each player is evaluated in real time. Top speed then means, the fastest measured single frame of a player/game.
28'
Fofana knock
The forward takes one to the head and will have to go off for some treatment.
26'
Water break
Time for a deserved refreshment break for both sides ...
25'
Dominant hosts
Possession (%)
6238
23'
Fofana effort
Trimmel releases Fofana, who thwacks one low at the target. Zentner gets a hand to the ball and Mainz survive.
Union heads up
© Getty
17'
Fofana electric
David Datro Fofana - on loan at Union from Chelsea - is looking particularly busy on his Bundesliga debut. The 20-year-old looks to scamper away down the left but is just muscled out of possession.
16'
100 per cent Irons
Goal attempts
0off target
2on target
0off target
0on target
14'
Union Record
Kevin Behrens's quick-fire opener in the first minute here was the fastest goal in Union's Bundesliga history at the Stadion An der Alten Försterei.
12'
Busy Behrens
Union's No. 17 has picked up a booking to go with his two goals. An incident-packed opening to this game for the 32-year-old.
9'
Union in Behrens heaven
Bo Svensson will be furious with he Mainz defence, but Union's fans couldn't care less about that. Keven Behrens has his hand raised in celebration after another headed goal. Aissa Laidouni's cross from the right is met by the rising, unchallenged Behrens, who nods in his, and Union's second.
Goal probability
Goal probability
Goal probability determines the likelihood that the ball will land in the goal from every position on the pitch. The value is based on large amounts of data from previous years; factors such as shot angle, distance to goal and opponent pressure - as well as mathematical models.
6'
Over eager Fofana
Fofana lands a foot on Stach and the Mainz man crumples to the floor. That looked painful. Fofana receives a word from the referee.
3'
Mainz probing
Mainz look to hit back immediately with Ajorque and Da Costa menacing. No way through doing this time for the 05ers.
1'
What a start!
Incredible Union. Brenden Aaronson frees Jerome Roussillon down the left and when the accurate centre comes into the area, Kevin Behrens glances a perfect header across Robin Zentner and into the far corner. Superbly-taken goal.
Goal probability
Goal probability
Goal probability determines the likelihood that the ball will land in the goal from every position on the pitch. The value is based on large amounts of data from previous years; factors such as shot angle, distance to goal and opponent pressure - as well as mathematical models.
1'
Game on!
Away we go! Urs Fischer's Champions League army get today's Bundesliga game underway ...
Kick-off!
Perfect day for football
The sun is shining brightly down on the German capital and the Stadion An der Alten Försterei is already rocking. The Union Berlin club anthem is currently belting out as we await the two teams. Not long to go now ...
Fischer focused
© Imago
Mainz experience
With an average age of 28.6 years, today's visitors are fielding their oldest starting XI in nearly a decade. The last time the 05ers sent an older side into the mix was back in October 2013 in a 2-0 win against Eintracht Braunschweig.
Mainz team news
Mainz knocked Elversberg out of the DFB Cup at the first round stage last week and coach Bo Svensson has decided to stick with the side that started that win here. Jonathan Burkardt, Silvan Widmer and Andreas Hanche-Olsen all continue to recover from injury while recent signings Sepp van den Berg and Tom Krauß are on the bench for the 05ers.
Union team news
Union are showing three changes to the side that began last weekend's 4-0 DFB Cup first round win against FCA Walldorf. Rani Khedira is injured while Sheraldo Becker and Josip Juranovic drop to the bench. That means starts for Christopher Trimmel and new arrivals Alex Kral and USMNT international Brenden Aaronson. David Datro Fofana makes his Bundesliga debut up top while Kevin Volland and Robin Gosens are among the Union subs.
Union starting XI
Ronnow – Doekhi, Knoche, Leite – Trimmel (c), Kral, Laidouni, Roussillon – Aaronson, Behrens, Fofana
Union subs
Schwolow, Gosens, Jaeckel, Juranovic, Kemlein, Pantovic, Volland, Jordan, Becker
Mainz starting XI
Zentner (c) – Bell, Kohr, Fernandes – da Costa, Stach, Barreiro, Caci – Lee, Ajorque, Onisiwo
Mainz subs
Rieß, van den Berg, Leitsch, Krauß, Papela, Barkok, Gruda, Mamutovic, Weiper
Mainz after consistency
Today's visitors to Berlin, who denied Dortmund the title on the final day of 2022/23, flirted with Europe last season before imploding down the final stretch. Victory over Bayern on MD29 was their sixth during a 10-game unbeaten run but they subsequently lost four on the spin before holding BVB. More of the former will see a European push, the latter would result in a relegation battle.
12:00
Watch: This is Union
How do Union keep improving?
© Getty Images
2:00
Watch: The Bundesliga is back!
Probable line-ups
© Imago
2:03
Watch: Previous meeting - Union 2-1 Mainz
On the up
Mainz set a new club scoring record last season with 54 goals. Bo Svensson's men were never in danger of relegation and were never in the bottom third of the table.
Favourite opponents
Union have scored more goals against Mainz (15) than they have against any other side. They also have their best overall goal difference against the 05ers (+8).
Tough nut to crack
Union are unbeaten in their last four meetings with Mainz, winning three and drawing one.
0:30
Watch: Get ready for Union vs. Mainz!
4:45