After four months away from the courts following a doping ban, Marin Cilic felt like a kid playing for the first time at the Paris Masters on Monday.
The Croatian, whose ban was reduced from nine to four months by the Court of Arbitration for Sport (CAS), was overjoyed just to be able to play again while beating Dutchman Igor Sijsling 5-7, 6-1, 6-4 in the first round.
"I felt like a kid playing for the first time," Cilic said.
"The feeling was amazing just to be back on the court, to be competing and I enjoyed every moment.
"My thoughts were just on how much I am enjoying it and how I am happy to be back on the court."
Cilic was initially banned for nine months in September after the International Tennis Federation (ITF) said he had failed a test for the banned stimulant nikethamide.
On Monday he explained that he had tested positive for the metabolite of nikethamide.
"It shows that nikethamide was in the system some time before and it's completely inactive and doesn't have any effect on the body," he said.
"I'm definitely waiting for the CAS decision in writing and waiting what the ITF will say with all these things
World No 1 Rafa Nadal said he was happy that Cilic had returned to competitive tennis.
"The only thing that I can say is that I am happy to see Marin back on tour," he told a news conference.
"He's a good guy and a great player. I don't know what happened, but if he's back, it's because it's fair that he's back. That's all. Happy for that."