Marcus Rashford opened the scoring in the first half, as he met Daniel James’ cross to fire past Alisson from close range.
United appeared to be on course for a much-needed victory, but Adam Lallana met Andy Robertson’s cross from the left to equalize.
Giggs believes Rojo, who replaced Axel Tuanzebe in the starting line-up, should have done better to stop the Liverpool midfielder from scoring.
“[Aaron] Wan-Bissaka has not played a lot of games, maybe if he was a little bit fitter and sharper he would have got out quicker.
“But for Rojo to actually go past [Harry] Maguire is strange. If he holds his position maybe he can clear it.
“Ash [Young] never really gets goal-side.
“But if you watch Rojo he just anticipates where the ball is going to be instead of staying with his man.
“I think it’s a poor goal to give away.
“But Liverpool, for that five and ten minutes, were knocking at the door and there you see Robertson crossing the ball a lot further up the pitch.
“Where for the majority of the game, him and Trent Alexander-Arnold were crossing the ball from 40, 45 yards out,” Giggs told Optus Sport.
