Novak Djokovic has brought in Poland’s Wojtek Fibak to his team on a trial basis at the U.S. Open. A former Top 10 player who reached the French Open, Wimbledon, and U.S. Open quarterfinals in 1980, Fibak once coached Ivan Lendl.

“It was a team decision,” Djokovic told reporters at the U.S. Open. “I never try to make decisions on my own, because even though it’s individual sport, it’s a team effort in the end that really counts. So we discuss everything that is on our agenda basically. We all agreed that we might need that extra help, and consultation. Wojtek Fibak was the right person for us at that moment. We will see how it will go during these two weeks.”

Djokovic’s current team is headed by longtime coach Marian Vajda, and also includes physiotherapists Milan Amanovic and Gebhard Phil-Gritsch. The top-ranked Serbian has not won a title since Monte Carlo in March.