World number one Novak Djokovic is out of the Srpska Open thanks to a straight-set defeat by fellow Serb Dusan Lajovic in the quarter-finals.
Djokovic, 35, was beaten 6-4 7-6 (8-6) by the world number 70 in Bosnia-Herzegovina.
It is a further blow to Djokovic as he builds up to next month’s French Open.
Meanwhile, Britain’s Dan Evans is through to the Barcelona Open semi-finals after beating Argentina’s Francisco Cerundolo 2-6 7-5 6-3.
British number two Evans has now reached the semi-finals in two of his last three tournaments after reaching the last four in Marrakech at the start of April.
He faces top seed Carlos Alcaraz next after the 19-year-old US Open champion beat fellow Spaniard Alejandro Davidovich Fokina 7-6 (7-5) 6-4 in their quarter-final.
Lajovic’s reward for beating Djokovic at the Srpska Open is a semi-final against another Serb Miomir Kecmanovic, who beat Jiri Lehecka of the Czech Republic 7-5 6-0 to reach the last four.
“I’m overwhelmed,” said Lajovic. “It’s the biggest win of my career. Beating him is something I didn’t even think was possible, but it happened.”
Djokovic, who suffered a shock defeat by Lorenzo Musetti at the Monte Carlo Masters last week, has been troubled by a right elbow problem.
The 22-time Grand Slam champion had surgery on the joint in 2018 and said it was “not in an ideal condition” going into the Srpska Open, though he did not wear any strapping against Lajovic like he did in the defeat by Musetti last week.
It was just Djokovic’s second tournament since early March, having missed Indian Wells and the Miami Open after being denied entry to the United States.
He will begin his quest for an overall men’s record 23rd Grand Slam title at Roland Garros on 28 May.
Swiatek sets up rematch with Jabeur
In Stuttgart, world number one and defending champion Iga Swiatek beat Karolina Pliskova 4-6 6-1 6-2 to set up a US Open final rematch against Ons Jabeur in the semi-finals.
Poland’s Swiatek quickly went 4-0 down as the 31-year-old Czech took the first set.
But Swiatek, 21, replied in similar fashion, winning the first four games of the second set to level the contest and then breaking early in the decider to take the match.
Jabeur, the Tunisian world number four, defeated Beatriz Haddad Maia of Brazil 6-3 6-0.
Swiatek beat Jabeur in straight sets in the US Open final last year as she won her second major of 2022.
“The good thing maybe, Iga is not at the same level as she was last year,” said Jabeur.
“I think maybe the key is to be unpredictable with Iga, not knowing which shots I’m going to do. I think that’s really good to disturb her a lot.”
World number two Aryna Sabalenka, who came from a set and a break down to beat Spanish wildcard Paula Badosa, will face Anastasia Potapova in the other semi-final.
The Russian beat French fourth seed Caroline Garcia 4-6 6-3 6-3.
