Daniil Medvedev fought back to beat Germany's Jan-Lennard Struff 4-6, 6-4, 6-3 in the second round of the Shanghai Masters on Saturday, the Russian's first match since being disqualified from the China Open.
Medvedev was defaulted from his semifinal against Novak Djokovic in Beijing for hitting a spectator with a ball and ended the 500-level event with zero ranking points and no prize money.
The former world No 1 said it was an accident.
Playing five days later in Shanghai, sixth-ranked Medvedev overcame an early wobble to hold off 59th-ranked Struff.
He sent down 21 aces to advance.
"When I broke him I felt like I could win it," the 30-year-old Medvedev said of a dominant third set in which he despatched a masterful backhand volley during the sixth game that helped him go up 4-2.
The court was "different from Beijing", he told an on-court interviewer, adding "it was a bit tough to get used to".
He faces either Czech qualifier Dalibor Svrcina or Tomas Martin Etcheverry of Argentina in the next round.
Later on Saturday, second-seeded Carlos Alcaraz was due to start his title bid in Shanghai against Juan Manuel Cerundolo in the second round.