Fellow back rower Ben Skirving crossed with two minutes to go to give Saracens a 20-16 win at The Stoop.
And Gaffney was quick to play down an injury scare after Hill was substituted late on.
He said: "Hill was limping a bit at the end but he'll be fine in three or four days.
"That limp will disappear and it is not necessarily because of the fact he's suffering from it, it maybe just mental.Â
"I thought that Hilly was very, very good for us tonight.Â
"By self admission he fell off probably more tackles tonight than he's fallen off for a long time.
"He's absolutely on track and his experience would bring a lot to England just because he's Richard Hill.
"You could say that Harlequins may have deserved to win that game - the plus for us is the fact that we ground out a win."