Hart played on after suffering a cut close to the eye to make a number of crucial saves as City claimed top spot in the Barclays Premier League with a hard-fought 1-0 win at the Etihad Stadium.
A club official later confirmed Hart had needed five stitches after being hurt in a collision with Palace striker Cameron Jerome during the first half.
Pellegrini, who had been unaware stitches were needed as he gave his post-match press conference, said: "It was not a serious problem. The doctors said he doesn't have serious problem. There isn't a problem with his sight."
Hart was dropped by Pellegrini at the end of October after a series of high-profile errors for club and country.
Costel Pantilimon took his place for seven Premier League games and Pellegrini believes the break has done Hart good.
He said: "I repeat what I said last week, it was very good for Joe Hart to have a rest.
"He needed a rest and he is playing at his normal performance level, as the good goalkeeper he is.
"He worked very hard but he was always confident he would return to his position."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball