Three-time grand slam champion made a premature exit from Australian Open, but has since been winning again
Stan Wawrinka says 'level is getting better' after reaching Sofia Open semi-finals
Stan Wawrinka said his game was back on the up after seeing off Viktor Troicki in straight sets to reach the semi-finals of the Sofia Open on Friday.
The Swiss suffered a second-round exit from the Australian Open last month in what was his first competitive match since Wimbledon, having undergone knee surgery last summer.
However, the three-time grand slam champion has now strung back-to-back victories together in Sofia to reach the last four, following up his three-set win over Martin Klizan with a 6-1, 7-6 triumph over sixth seed Troicki on Friday.
"I think my level is getting better. I'm serving and moving better and it's a great win for me," Wawrinka, who is chasing the 17th tour-level title of his career, said on atpworldtour.com. "I'm enjoying my time, I'm fighting on the court and that's the most important."
Wawrinka will face Mirza Basic for a place in the final after the Bosnian defeated Maximilian Marterer 6-4, 4-6, 6-3.
Romania's Marius Copil reached his first ATP World Tour semi-final after upsetting third seed Gilles Muller 6-4, 6-4.
Copil will now take on Slovakian qualifier Jozef Kovalik, who defeated Marcos Baghdatis 7-6, 6-4.
In Montpellier, top seed and world No 7 David Goffin had little trouble seeing off Karen Khachanov in their quarter-final encounter.
Goffin did not face a single break point while fashioning 11 of his own en route to a 6-4, 6-4 win over the Russian.
The Belgian may find things a little tougher now, though, with his next opponent being home hope Richard Gasquet, who boasts a formidable record in this tournament.
The Frenchman, seeded fifth, was champion here in 2013, 2015 and 2016 and is looking to reach the final for a sixth successive year.
He moved a step closer to achieving that feat with a 6-4, 6-2 win over fourth seed Damir Dzumhur - improving his record to 21 victories in 23 matches in Montpellier since 2013.
Extra Time podcast: Will floodgates now open for Caroline Wozniacki?
His compatriot Jo-Wilfried Tsonga, the third seed, is also through after beating sixth-seeded Russian Andrey Rublev 6-4, 7-6.
Tsonga's next opponent will be second-seeded Lucas Pouille, who beat fellow Frenchman Benoit Paire 6-1, 6-4 in less than an hour to complete the semi-final line-up.
Two qualifiers have made it to the semi-finals at the Ecuador Open on another day of upsets.
Spain's Roberto Carballes Baena defeated eighth seed Nicolas Jarry, overcoming 14 aces from the Chilean to win 3-6, 6-2, 7-6.
He will next face fellow qualifier Andrej Martin, who knocked out Frenchman Corentin Moutet 6-3, 6-4.
No 3 seed Gael Monfils was also dumped from the competition, losing 6-4, 2-6, 6-4 to world No 118 Thiago Monteiro.
However, second seed Albert Ramos-Vinolas has emerged as a favourite for the title after toppling Austria's Gerald Melzer 6-2, 6-4.
The Spaniard won 70 per cent of the points on Melzer's second serve to help him reach his third semi-final in Quito.