The younger brother of Alejandro Garnacho has claimed that the Manchester United attacker was only able to train for two days last week due to a hamstring problem.
The 19-year-old played the full 120 minutes of Man United's 4-3 victory over Liverpool in the quarter-finals of the FA Cup on Sunday afternoon, and he provided the assist for Amad Diallo to win it for the Red Devils late on.
Garnacho has been a vital player for Erik ten Hag's side this season, making 37 appearances in all competitions, scoring seven goals and registering three assists in the process.
According to Roberto Garnacho, the Argentina international could only train for two days in the build-up to the Liverpool clash, making his display against the Reds even more impressive.
"Garnacho has trained two days this week due to a hamstring injury, still he is there running 120 minutes and giving the winning assist. I'm proud of you BIG BRO," read a post from Garnacho's brother on X.
Man United trailed 3-2 against Liverpool in the 105th minute of the contest, but Marcus Rashford levelled the scores in the 112th minute before Amad netted the game's winning goal in the final exchanges.
Garnacho will now link up with the Argentina squad for their March friendlies with El Salvador and Costa Rica, before returning to club duty with a trip to Brentford on March 30.
Man United head coach Ten Hag said after Sunday's match that young talents like Garnacho demonstrate that the club have a bright future.
"To go to the final we have to win against Coventry [City], we will have to play at our best. We saw that Coventry have great spirit, a great mentality. We will prepare our best to play in the final," Ten Hag told ITV Sport.
"The first 30 minutes was the best of our whole season, we were acting as a team but then we got gaps between the lines and you can't allow this against one of the best teams in Europe. They outplayed us.
"Then we made changes, we took risks and the players were wonderful. The attitude was great, a strong belief to win this game.
"Rashford is resilient, he keeps going, normally he finishes those moments but he kept going for another chance. That inspired the other players.
"We have a team that is for the future. Coming up are players who are developing very well like Diallo, Garnacho, Kobbie Mainoo."
Man United are now one game away from the FA Cup final, with Championship outfit Coventry their opponents, while the second semi-final will see the holders Manchester City face Chelsea.
