ROTTERDAM, NETHERLANDS (REUTERS) - Spain's Pablo Carreno Busta overcame a gritty challenge from Italian Jannik Sinner to win 7-5 3-6 7-6(6) in a marathon clash to reach the Rotterdam Open semi-finals on Friday (Feb 14).

Carreno Busta squandered three match points while leading 5-4 in the final set before saving two himself at 6-4 down in the tiebreak to advance in two hours and 45 minutes and set up an encounter with Canadian teenager Felix Auger-Aliassime.

"It was very tough mentally to continue fighting on every point," said Carreno Busta, who won his third consecutive three-setter at the tournament.

"I know that I lost a lot of opportunities to close out the match.

"I didn't play good points, I was playing too slowly and not aggressively. But after that I continued fighting very well and saved two match points playing aggressively in the tiebreak. It was a very important match to win."

Auger-Aliassime beat Slovenia's Aljaz Bedene, despite being unwell and looking out of sorts, winning 6-4 7-6(6).

The 19-year-old broke Bedene at 5-4 to take the first set and looked firmly in control in the second before the Slovenian picked up his game to force a tiebreak with well executed points designed to tire out the struggling Auger-Aliassime.

However, the visibly exhausted Canadian managed to save a set point before winning the tiebreak and advancing to only his third career ATP 500 semi-final.

French third seed and defending champion Gael Monfils is in action against Briton Dan Evans later on Friday.