Behrens grabs hat trick, Rönnow saves 2 penalties as Union Berlin beats Mainz in Bundesaliga opener #Behrens #grabs #hat #trick #Rönnow #saves #penalties #Union #Berlin #beats #Mainz #Bundesaliga #opener

BERLIN (AP) — Kevin Behrens scored a hat trick and Frederik Rönnow saved two penalties for Union Berlin to start the new Bundesliga season with a comfortable 3-1 win over Mainz on Sunday.

United States midfielder Brenden Aaronson started for his league debut and was involved in the opening goal as he sent Jérôme Roussillon through with a clever backheel. Roussillon crossed for Behrens’ first headed goal in the first minute.

Aïssa Laïdouni crossed for Behrens’ second in the ninth, and substitute Sheraldo Becker crossed for his third in the 70th.

Substitute Miloš Pantović wrapped up the scoring with the last kick of the game.

Dortmund's players react after the German Bundesliga soccer match between Borussia Dortmund and FSV Mainz 05 in Dortmund, Germany, Saturday, May 27, 2023. (AP Photo/Michael Probst)

Bayern Munich players celebrate winning the German championship after the German Bundesliga soccer match between 1.FC Cologne and FC Bayern Munich in Cologne, Germany, Saturday, May 27, 2023. (AP Photo/Matthias Schrader)

Mainz defender Anthony Caci had scored with a fine volley in the 64th, prompting Union coach Urs Fischer to make a double substitution with Robin Gosens coming on for his debut along with Becker, who effectively sealed the result with his precise cross for Behrens.

Aaronson, on loan from relegated Leeds, was one of three new signings who started for Union along with Czech Republic midfielder Alex Kral and Nigerian striker David Datro Fofana. It was the 22-year-old Aaronson’s fourth league debut in five years after his stints at Philadelphia Union (MLS), Salzburg (Austrian Bundesliga) and Leeds (Premier League) before coming to Union.

Fofana, on loan from Chelsea, impressed by threatening Mainz defenders with his pace. Fofana saw a powerful shot saved by Mainz captain Robin Zentner, and struck the crossbar with a free kick in the 33rd.

Union’s defense coped with the visitors’ attempts to pull a goal back, and Zentner produced a flying save to deny Diogo Leite before the break.

The second half sparked to life when Leite conceded a penalty for a foul on Brajan Gruda. Rönnow saved Ludovic Ajorque’s spot kick in the 62nd, then repeated the feat in the 88th.

Eintracht Frankfurt was hosting promoted Darmstadt for a derby in the late game with Randal Kolo Muani in the starting lineup. Frankfurt had reportedly turned down a 65 million euro ($71 million) offer from Paris Saint-Germain for its star forward and was holding out for 100 million ($110 million).