Leeds United scored two second-half goals to beat Sheffield Wednesday 2-1 at the weekend.
Sharp came off the bench with the scores locked at 1-1, but his arrival sparked an immediate improvement from his side and helped Steve Morison score the winner.
It was a display which may have seen him force his way into the Whites' team for the final day of the season and Gray felt that his partnership with Morison was an effective one.
"It's a great victory in a local derby," he said. "I thought we came out in the second-half and were the better side. Billy Sharp came on and looked lively and Steve Morison did well.
"Mind you, if he hadn't stuck the rebound in the back of the net I think Neil [Redfearn] would have had something to say as he had Charlie Taylor right in front of the goal!"
Sharp's first season at Leeds has been a frustrating one so he will be pleased to be earning praise from Gray.
The former Southampton man has generally disappointed and he has failed to live up to expectations at Elland Road this season, with his clinical finishing not on display.
Sharp was brought to Leeds to be the man tasked with scoring the bulk of their goals, but he has struggled to make an impact.
The 29-year-old has netted just five times and he will realise that he will need to have a much better campaign next time around if he is to remain at Leeds for much longer.