Sanchez finally put pen to paper on a long-term contract with the Red Devils on Monday after the relentless speculation linking him with a move to Old Trafford from Arsenal.
The 29-year-old moved to Old Trafford as part of the deal which saw Henrikh Mkhitaryan head to Arsenal, which was also officially announced on Monday.
Sanchez will now look to quickly settle into life at Old Trafford and he could even make his debut for the club on Friday night, when the Red Devils take on Yeovil Town in the fourth round of the FA Cup.
De Gea has been earning huge amounts of praise for his fine performances for Manchester United so far this season.
And Sanchez has admitted that he respects De Gea as one of the best shot-stoppers around on current form.
Speaking in an interview with MUTV, Sanchez said: “I’ve not had the chance to get to know them personally or spend time with any of my team-mates up to now, but of course I know them from having played against them in the past.
“I believe that David De Gea is one of the best goalkeepers in the world right now.
“He’s a player who I’ve always found it hard to score past, and so for me he is right up there with the best keepers in the world.”
Sanchez joins Manchester United with the Red Devils in second place in the Premier League table and 12 points behind leaders Manchester City.
The Chile international helped Arsenal win two FA Cups during his four-year stint with the Gunners.
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