Rafael Nadal insists injury was not a factor after he was beaten in straight sets by Alexander Zverev at the ATP Finals.
Nadal came into the match with concerns about his fitness after suffering an abdominal strain last weekend.
But after a week of rehab, Nadal was able to take to the court against Zverev at the O2 Arena.
However, Zverev, the defending champion was in top form from the outset, especially on serve.
The German broke Nadal twice in the first set and a single break in the second set was enough to seal a 6-2 6-4 victory.
Nadal’s serve regularly around the 120mph mark and his movement did not appear to be restricted.
And in his post-match press conference, the Spaniard made clear the abdominal injury was not the issue, just a lack of practise.
He said: “Good, no complaint about the physical condition. No pain in abdominal. That’s the only positive thing, honestly. That’s all.
“Happy the way that abdominal hold, and hopefully I can continue like this, because it’s true that I was not able to create a lot of practice and a lot of effort on that part of the body since last Saturday.
“So is a positive thing that I hold the whole match today. Hopefully I can keep going, and hopefully, I can practice a little bit more tomorrow.
“We had to do the things step by step, step by step being very, you know, a big precaution in all the movements that we have been doing since last Saturday, and today I’m fine.
“So the physical issue was not an excuse at all. The only excuse is I was not good enough tonight.”
For Zverev, it was his first win over Nadal at the sixth attempt and he was delighted to make a winning start to the tournament.
“It is great. Obviously everyone knows how much I was struggling the whole season and this means so much playing here again,” Zverev said.
“After winning the biggest title of my career here last year this place means so much to me.
“I was looking forward to this match and thanks a lot to everyone that came out and supported me.
“This is why, the atmosphere, at the beginning of the season everyone is trying to make London. Playing here in front of you guys is something we don’t have during the year. This is so special and thank you very much.