Grigor Dimitrov edged closer to his first appearance at the ATP World Tour Finals on Saturday as he booked his place in the Stockholm Open final.

The Bulgarian moved into fifth in the qualification places for the season finale in London with a 6-3 7-6 (7-2) victory over sixth seed Fabio Fognini.

After only dropping six points on serve in the opening set, Dimitrov – champion in 2013 – looked like he would have a fight on his hands when Fognini reeled off four games in a row to lead 4-2 in the second.

Dimitrov battled back to force a tie-break and took control to secure a spot in the final, where he will meet defending champion Juan Martin del Potro.

The 26-year-old's win moved him ahead of Marin Cilic in the Race to London, boosting his chances of joining Rafael Nadal, Roger Federer, Dominic Thiem and Alexander Zverev at the O2 Arena next month.

Del Potro's path to the final was much tougher as he needed to come from a set down to beat Fernando Verdasco 6-7 (4-7) 6-4 7-6 (7-1) in a thrilling semi-final.

It took nearly an hour for Verdasco to move ahead but it only served to fire up Del Potro and soon he was level, a break early in the second enough for the Argentine.

Both men wasted break chances in the decider but it was Del Potro who earned the only two match points of the clash and broke his opponent on the second to book a meeting with Dimitrov, who he beat at this stage 12 months ago.

Sunday will see Jo-Wilfried Tsonga go up against Diego Schwartzman for the European Open crown after both recorded straight-set semi-final wins.

Tsonga converted all four break points against Rubens Bemelmans in Antwerp and will get the chance to add to the three titles he has already won in 2017.

He will face world number 26 Schwartzman after the Argentine twice battled back in an enthralling second set to beat Stefanos Tsitsipas 6-3 7-5.

The Kremlin Cup final in Moscow, meanwhile, will be contested by Ricardas Berankis and Damir Dzumhur, the latter winning a second-set tie-break 11-9 to beat best friend Mirza Basic.