2014 champion loses to Sebastian Baez in final tournament appearance in Monaco.

Stan Wawrinka’s farewell to the Monte Carlo Masters ended on Monday as the 2014 champion fell 7-5, 7-5 to Sebastian Baez in the first round.

The 41-year-old three-time Grand Slam winner, who will retire at the end of the season, entered the main draw as a wild card, 20 years after his debut at the tournament.

Wawrinka claimed his only 1000-level title in Monaco in 2014, defeating fellow Swiss Roger Federer. On court, he reflected on the victory after tournament organisers presented a video tribute.

"It was a long time ago, but of course I remember it, it was exceptional," Wawrinka said. "To have the chance to play this final here, with this exceptional tournament, and to win it in addition, will always be one of my best memories of my career."

Before facing 65th-ranked Argentinian Baez, Wawrinka’s only match since February’s Dubai Open was a three-set loss to world number 348 Matteo Martineau at a challenger event in Naples last month.

Wawrinka started strong on Court Rainier III, taking a 4-1 lead in the opening set, but Baez fought back to level at 5-5 and then broke Wawrinka’s serve to gain the advantage. Baez took control in the second set, winning in one hour and 47 minutes despite a late rally from the former world number three.

Baez will now face world number one and reigning Monte Carlo champion Carlos Alcaraz in the second round.

Elsewhere in Monaco, 13th seed Andrey Rublev survived a rollercoaster opening match, beating Nuno Borges 6-4, 1-6, 6-1 to face Zizou Bergs in the round of 32. Bergs, ranked 47th, defeated 37-year-old Adrian Mannarino 6-4, 6-3.

Arthur Rinderknech also advanced with a 7-5, 6-2 victory over 12th seed Karen Khachanov and will play the winner of the match between Joao Fonseca and Gabriel Diallo.