Newcastle boss Eddie Howe says it was his call to not start Anthony Gordon against Barcelona due to ilness, after the winger received criticism from Alan Shearer.
Newcastle legend Shearer questioned why key forward Gordon only played a sub role in the Champions League last-16 first leg, which Howe had billed as the "biggest" in the club's history.
Newcastle ended up drawing the game 1-1, with Gordon coming on after 67 minutes.
The Magpies' record goal-scorer Shearer said on Amazon Prime: "I know he doesn't feel well, but this is Barcelona at Newcastle for a place in the quarter-finals of the Champions League.
"It would take something extraordinary to keep myself out of this game."
Shearer was backed by former Manchester United captain Roy Keane, who told The Overlap: "How can you be ill, but come on for half an hour?"
Howe said: "I do have to clear something up with Anthony Gordon. He was absolutely willing to play in the game against Barcelona.
"I know there's a lot of comments. It was my decision not to start him based on the fact that he'd been ill that morning and hadn't attended the training session.
"He was prepared to play, but in consultation with the medical team, he didn't think he was fit to play."
Gordon has played up front at times for Newcastle this season due to injury issues with team-mates. He has scored 10 goals in the Champions League but netted just four in the Premier League.
Asked about Gordon's character, Howe said: "Ant, I'd probably categorise him as a winner. He wants to win everything, he's a real competitor. He's got that streak to him that I think all top players need where he's very single-minded, very focused on his development and his game.
"I can only speak really glowingly of him this year. It hasn't been a straightforward season for him. He's had a lot of challenges, as every player does.
"But I think he's probably in the best moment that he's been this season currently. He's playing really well. He's played, obviously a different role for us, adapted to that really, really well.
"There's a lot of pressure on him and a lot of media attention on him and rightly so - he's an England international.
"He'll (have) his own aims and goals that he wants to achieve, but I think he's done really well."
Howe issues fitness updates on Wissa, Miley and Guimaraes
Howe says Yoane Wissa, who was an unused sub against Barcelona, is injury free, ahead of Saturday's trip to Chelsea in the Premier League, which is live on Sky Sports.
"Yoane is fit," said Howe. "Fitter, probably, than at any stage in his time with us. He's training with the group whenever we train and no injury concerns at all.
"The challenge for Yoane is, when introduced and on the pitch, he's got to perform."
Howe also said Lewis Miley is not currently training with the group but hope remains he'll be available for the second leg with Barcelona on Wednesday.
Meanwhile, Bruno Guimaraes is set to return from Brazil on Monday, where he has been receiving treatment on his hamstring injury.
"He's such a big player, so I'd love to think, by the time the international break has ended, he'll be back fit and available," said Howe.