The Red Devils signed Romelu Lukaku in a £75m deal from Premier League rivals Everton in the summer transfer window after seeing off competition from Chelsea.
The 24-year-old has helped the Red Devils to make an exciting start to the 2017-18 season thanks to a return of six goals in six games in the Premier League.
Manchester United netted 21 times in seven Premier League outings after a 4-0 win against the Premier League’s basement club Crystal Palace last weekend.
Bournemouth outscored Manchester United during Mourinho’s first season in charge of the Old Trafford outfit.
Former Spurs midfielder Jenas explained why the Red Devils will also prove a threat even when Manchester United aren’t playing well.
“It’s pretty simple with Manchester United,” Jenas told BBC Radio 5 Live. “They’re scoring goals. They change games.”
Manchester United finished in sixth place in the Premier League table last season.
The Red Devils signed Everton striker Romelu Lukaku, Chelsea midfielder Nemanja Matic and Benfica defender Victor Lindelof.
The 20-time English champions haven’t put a foot wrong in the Champions League following a 3-0 win against Basel before a 4-1 victory over CSKA Moscow.
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