The Belgium international started up front and set up goals for N'Golo Kante and David Luiz as Chelsea inflicted City's first league loss of the season with a 2-0 win on Saturday.
Sarri is open to using the 27-year-old, who has seven goals and eight assists in 15 league games this campaign, in the same role in the future.
"He had some problems at the beginning of the match, but I think he played really a very great second half. Maybe he deserved to score," he said.
"I think it's a very good option. We will play like today in the future for some matches of course."
Sarri's switch meant Alvaro Morata was left out of the squad, with Olivier Giroud starting on the bench.
The Italian said that was a purely tactical decision as he saw no reason to have two strikers among his substitutes.
"The reason was clear. We played with Hazard as a striker, so if we have to change something there was Giroud," Sarri said.
"I think it was useless to have two strikers on the bench and I prefer to have more midfielders.
"I was in trouble with the wingers. The only option was [Ruben Loftus-Cheek]. I prefer this."
The Blues boss was also impressed with the performance of defender David Luiz, who helped keep City's high-flying attack in check.
"I have to say I'm really very happy with him from the beginning," he said of the centre-back.
"Of course, there are matches like this one in which it's easier to stay in the defensive line. The defensive movements are working very well. And there are matches in which it's really difficult to stay in the defensive line, like Tottenham, because the defensive phase of the team is a disaster.
"Today he played a great match, but all the team helped him to play really well."
Chelsea are fourth in the Premier League after their win, eight points behind leaders Liverpool who took over top spot in the table thanks for City's loss and their own 4-0 win over Bournemouth on Saturday.