Andy Ruiz Jr admitted three months of partying and celebrating played a part in his defeat by Anthony Joshua on Saturday night.
The 30-year-old lost the world titles he won from AJ in June after a sluggish performance in which he never got close to the Brit.
:speaking_head:️ Andy Ruiz Jr apologises to his trainer Manny Robles and claims three months of partying affected him at the post-fight press conference. Robles responds by apologising back to him and vowing that he won't desert him now he's lost the Anthony Joshua rematch... pic.twitter.com/rf6mBDBgOE- Michael Benson (@MichaelBensonn) December 8, 2019
He shrugged off any concerns about carrying too much weight in the build-up, but after his loss he apologised to his trainer Manny Robles.
Ruiz Jr said: "My team were talking and I should've listened to them and not put on all this weight. I tried to do all this training on my own.
"I'm sorry, I should've listened to then more. I think I got too confident in myself but there's no excuses. He won one, I won one and I know for the third one I'm going to be a lot better.
"I think we started too late I don't want to say that three months of partying and celebrating I had affected me because to tell you the truth it kind of did."
Speaking to Sky Sports in the ring straight after the fight, Ruiz Jr said: "I didn't prepare how I should've and gained too much weight. He won and outboxed me but best believe if we do a third fight I'm going to get in the best shape of my life.
"I thought I was going to feel stronger and better but next fight I admit I'm going to be more prepared. I was chasing him instead of cutting the rings. I felt like I couldn't throw my combinations."
Joshua came in over three stone lighter than Ruiz Jr, and used his speed to cruise to a points victory in Saudi Arabia.
All training camp, Ruiz looked to be faster and scarier than when he knocked Joshua out in New York in June.
Ruiz Jr tried to shrug it off, saying: "I was already the same weight as the last fight this morning.
"I had to wait until almost 5pm to get on the scale, so I already had my breakfast, lunch and dinner. I also weighed in with my sombrero and pants on, so that's why I came in so heavy."
"It was a psychological thing as well."
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