Czech 30th seed Jiri Lehecka (22) became the latest player to withdraw in the Spanish capital through injury, as he sustained a back problem and was forced to retire at 3-3 in the opening set of his semi-final against Auger-Aliassime.

Top seed Jannik Sinner withdrew ahead of his quarter-final with Auger-Aliassime, citing a hip injury, while Jakub Mensik also gave the Canadian free passage when he retired early in the second set of their third round.

The Masters 1000 tournament in Madrid has been dealt one blow after another, starting with the pre-event withdrawal of world number one Novak Djokovic.

After losing Sinner to injury, the tournament also saw its third seed bow out as Daniil Medvedev retired midway through his quarter-final with Lehecka on Thursday.

Carlos Alcaraz, meanwhile, announced on Friday he was withdrawing from next week's Masters 1000 in Rome due to a forearm injury.

"It's crazy. I don't know if it's ever happened to a player before, it's kind of a weird situation to be in on my part," said a stunned Auger-Aliassime, who is through to the first Masters final of his career by playing just three completed matches.

Lehecka felt something in his back as he attempted a serve early in the match and took an eight-minute off-court medical timeout before play resumed at 3-3.

It was all over three points later as Lehecka fell to the ground in pain, bringing the match to an abrupt end.

"I couldn't believe what was happening when I saw that his back blocked on him. I feel really bad for him," said Auger-Aliassime.

"It's crazy times for the elite of our sport, withdrawing from many events. But obviously for me it's kind of a weird rhythm not having played that much and being in the finals. But I can just focus on the first week of tennis I had."

Rublev in 'right direction'

Rublev reached the fifth Masters final of his career with a 6-4, 6-3 win against American Taylor Fritz (26).

The seventh-seeded Rublev arrived at the tournament carrying a four-match losing streak but rebounded in the Spanish capital, claiming five impressive wins, including one over world number three Alcaraz in the quarter-finals.

"For sure mentally I was feeling much better (this week) and I was able to perform, putting emotions in the right direction, for sure that helped me to be in the final," said Rublev.

After getting broken in the opening game, Rublev recovered immediately and won the last seven points of the first set to take the lead in 39 minutes.

A break of serve in the sixth game of the second frame was enough for the Russian to complete a 72-minute victory.

Rublev leads his head-to-head 4-1 against Auger-Aliassime but four of their five encounters have gone to a deciding set. Auger-Aliassime lost their most recent clash in Rotterdam in February after holding three match points.

"We've always had three-set battles, even back in 2018, I was much younger," said the 23-year-old Canadian.

"He's always a player that fights hard, that's always present every tournament, us players have highs and lows but he's always there."