Marc-Andrea Huesler claims his maiden ATP Tour title on Sunday in Sofia.

Marc-Andrea Huesler in action on Sunday in Sofia.

David Vega Hernandez and Rafael Matos celebrate in Sofia on Sunday.

Holger Rune reaches his second ATP Tour championship match of the season on Saturday at the Sofia Open.

Marc-Andrea Huesler downs Lorenzo Musetti on Saturday to reach the final of the Sofia Open.

Jannik Sinner defeats Aleksandar Vukic on Friday in Sofia.

The officiating team at the Sofia Open.

Members of the Sofia Open tournament team and the officiating crew.

Holger Rune defeats Lorenzo Sonego on Thursday in Sofia.

Ilya Ivashka defeats Grigor Dimitrov in straight sets to reach the quarter-finals in Sofia.

Lorenzo Sonego downs Bernabe Zapata Miralles on Wednesday at the Sofia Open.

Holger Rune advances to the second round on tournament debut with victory against Tim van Rijthoven on Tuesday at the Sofia Open.

Top seed Jannik Sinner defeats Gael Monfils on Sunday to lift his third tour-level trophy of the season.

Top seed Jannik Sinner defeats Gael Monfils on Sunday to lift his third tour-level trophy of the season.

Jonny O'Mara and Ken Skupski defeat third seeds Oliver Marach and Philipp Oswald in the Sofia Open final on Sunday.

Top seed Jannik Sinner defeats Serbian Filip Krajinovic on Saturday to reach the Sofia Open final.

Frenchman Gael Monfils defeats Marcos Giron on Saturday to reach the final in Sofia.

Philipp Oswald and Oliver Marach defeat Santiago Gonzalez and Andres Molteni on Saturday in Sofia.

Jannik Sinner advances against James Duckworth on Friday to book a semi-final berth in Sofia.

Frenchman Gael Monfils overcomes Gianluca Mager on Friday in Sofia.

Marcos Giron defeats John Millman on Friday in Sofia to reach his first tour-level semi-final.

Philipp Oswald and Oliver Marach save four of the five break points they face to reach the Sofia semi-finals.

Jannik Sinner is the defending champion of the Sofia Open.

Jannik Sinner advances to the Sofia Open quarter-finals with a straight-sets win over Egor Gerasimov.

Marcos Giron defeats third seed Alex de Minaur on Thursday in Sofia to reach the quarter-finals.