A free-kick from Liverpool captain Steven Gerrard put the home side in front after 68 minutes but United substitute Javier HernÃ¡ndez salvaged a draw with a header in the 80th minute.
De Gea prevented the home side from snatching a dramatic winner when Dirk Kuyt prodded Stewart Downingâ€™s cross goal-wards, forcing a low save from Unitedâ€™s shot-stopper.
Moments later, the Spanish keeper showed superb agility to push Jordan Hendersonâ€™s lobbed attempt past the upright to ensure the visitors left Anfield with a point.
And Reina was impressed by his compatriotâ€™s performance, hailing the talent of the current crop of Spanish keepers.
“He made a couple of fantastic saves – it shows the potential of Spanish goalkeepers and we are very proud there are now two Spanish lads playing for Liverpool and Manchester United,” Reina told the Guardian.
Liverpoolâ€™s number one also backed his rival to find his form at Old Trafford despite De Gea making a number of mistakes already this season.
Reina feels that despite the former AtlÃ©tico Madrid goalkeeper being subjected to intense scrutiny in his short career at Old Trafford so far, De Gea will prove his quality.
“He will have poor performances, like all of us, but he will have a lot of good ones as well. It is about finding consistency, but he will do that because he is a talent,” Reina added.
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