Petrov was diagnosed with acute leukaemia on Friday, and the 32-year-old watched on from the stands as goals from James Collins and Eric Lichaj cancelled out Chelsea’s two-goal lead with 10 minutes remaining.
But the visitors responded, with Branislav Ivanovic netting his second of the game to give the Blues a slender advantage before Fernando Torres struck on the stroke of full-time to seal a vital win for Chelsea.
“The players responded well, Stan came in to see us before the game, we gave him a hug, and said it’d be nice to win it for Stan,” said McLeish.
“We gave everything, it’s a shame we’re not talking about a win as we felt we had Chelsea on the ropes.
“It was quite an emotional moment, a show of strength and support from the Villa fans.
“We’ve got to support Stan, he’s started his recovery, and I’m sure he can fight it and beat it.”
Chelsea surged into a first-half lead when good interplay between Juan Mata and Torres provided Daniel Sturridge with a simple close-range finish.
The Blues then extended their advantage in the 51st minute when Villa failed to adequately clear Mata’s corner and Ivanovic poked his finish past Shay Given.
McLeish’s side offered very little but remarkably found themselves level 10 minutes from time after Collins and Lichaj scored in a frenetic four-minute spell.
But Chelsea hit back and Ivanovic netted from another corner before Torres raced onto Sturridge’s pass and squeezed his finish past Given in the 88th minute to secure the win.
“I thought it was an exciting game, we controlled it very well apart from five minutes,” said Chelsea caretaker boss Roberto Di Matteo.
“I credit the opposition with playing well. We conceded from a long throw but we thoroughly deserved to win.
“We were dominating the game, controlling it and a third goal could’ve killed it off earlier but credit to Villa. Historically it has proven a difficult place to come for us.
“We’re delighted to score four goals and apart from five minutes we were a good team.”
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