The 22-year-old came off the bench in the second half to find the net with an instinctive finish to extend England’s lead to three goals.
Rashford has been in red hot form for the 20-time English champions over the past couple of months.
The Manchester United striker has netted nine times and has made one assist in his last 10 games for club and country.
Rashford’s form will come as a relief to Ole Gunnar Solskjaer given Manchester United’s lack of options up front at present.
Former Manchester United captain Keane was impressed with Rashford’s quality finish in England’s 4-0 rout of Kosovo.
“Brilliant, brilliant goal,” Keane said during ITV’s coverage of England’s win.
“What a finish. He is back to his best. It was a lovely play, nice and simple. Does it matter about the opposition? Of course it does, because they’re getting opportunities, but that was the goal of the night. A lovely finish. Pure quality.”
Keane went on to say that England boss Gareth Southgate has three excellent options to lead his attack in the shape of Rashford, Harry Kane and Raheem Sterling.
Keane added: “The attacking three players you’d have at the minute are [Raheem] Sterling, [Harry] Kane and Rashford. The three of them are outstanding players who cause you all sorts of headaches.”
Rashford will be hoping to extend his prolific run when Manchester United take on Sheffield United on Sunday.
The Red Devils are in seventh position in the Premier League table and nine points adrift of fourth-placed Manchester City.
Manchester United will be hoping to improve upon their sixth-placed finish last term after Solskjaer replaced Jose Mourinho midway through the season.
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