Ibrahimovic continued his goal-scoring run with the opener in the 36th minute after the 34-year-old rose above Jose Fonte and guided a header past England goalkeeper Fraser Forster.
The former Paris Saint-Germain centre-forward added his second from the penalty spot after ex-Southampton left-back Luke Shaw was fouled inside the area.
Match of the Day host Lineker took to Twitter to deliver his verdict on Ibrahimovic’s second Premier League game after the Swedish legend took his Premier League tally to three goals.
It's not taken too long for Ibrahimovic to adapt to the @premierleague . Class act!
— Gary Lineker (@GaryLineker) August 19, 2016
The Red Devils were 3-1 winners against Bournemouth in their opening Premier League game of the season last weekend thanks to goals from Juan Mata, Ibrahimovic and Wayne Rooney.
United are at the top of the Premier League table and three points clear of second-placed Liverpool following their comfortable win against the Saints.
Mourinho’s side will make the trip to promoted side Hull City in their next Premier League game on Saturday 27 August.
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