The Spain international was on the brink of a £25m move to Real Madrid last summer before the proposed deal fell through on La Liga’s deadline day.
De Gea has since put pen to paper on a new long-term contract with the 20-time English champions but speculation continues to surround his long-term United future.
The 25-year-old made six saves to limit Liverpool to two goals as Jurgen Klopp’s side were 2-0 winners against United in the first leg of their Europa League last-16 clash on Thursday night.
Speaking to ITV Sport following the resounding defeat on Merseyside, former United striker Saha explained why he is worried about De Gea’s future.
“I’m not in his position. It is a big call,” Saha said.
“When a big club like this comes and you’re not feeling like you’re going to play champions league week in, week out, it is something you have to look at.”
Saha added that Louis van Gaal should be worried his best players is consistently his goalkeeper ahead of Sunday’s FA Cup quarter-final against West Ham United at Old Trafford.
“It is a bad sign. It should be strikers who should be our best players,” Saha added.
“You can have great goalkeepers who make great saves and save you points. But it isn’t normal.”
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