Klich leaves Leeds to sign two-year deal with DC United
Klich has signed a two-year contract with an additional option for 2025 and should strengthen a team which finished with the worst record in the league last season.
“Mateusz is a first-rate midfielder who will add top-level experience to our roster," Rooney said.
"I've been watching him since he helped lead Leeds to promotion to the Premier League and his vision, range of passing, and scoring ability will be a huge asset for us this season," he added.
The 32-year-old Klich played in Germany and the Netherlands before moving to Leeds where he was a key part of Marcelo Bielsa's promotion-winning team in 2020.
Klich has made 41 appearances for Poland's national team.