Stefanos Tsitsipas's post-French Open gloom deepened Friday when the world number four slumped to a European Open quarter-final defeat to Serbia's Filip Krajinovic.

Tsitispas, who gave up a two-set lead to lose the Roland Garros final to Novak Djokovic last month, went down 3-6, 6-1, 6-3.

The Greek star won the first 11 points of the match before being reeled in by Krajinovic who goes on to face countryman Laslo Djere for a place in the final.

Tsitsipas has struggled since the French Open, losing in the first round at Wimbledon against Frances Tiafoe of the United States before seeing off Dominik Koepfer of Germany in his opening match in Hamburg.

Djere booked his semi-final spot by defeating third-seeded Georgian Nikoloz Basilashvili 6-2, 6-2.