The Red Devils have struggled when Pogba has been missing from the Manchester United team in the 2017-18 season so far.
Pogba scored two goals and made two assists in his opening four Premier League games before the club record signing suffered a serious hamstring problem.
The 25-year-old returned to the Manchester United side for the visit of Newcastle United and the versatile midfielder made one goal and scored his third of the season.
Pogba produced one goal and five assists during a six-game run in all competitions before a reckless challenge on Hector Bellerin resulted in a straight red card and a three-game suspension.
Manchester United struggled with one win in four games in October before Pogba’s return to prove his imprortance to Jose Mourinho’s men.
Former Republic of Ireland defender Cunningham believes Mourinho needs to spend big to bridge the gap between the two Manchester clubs and find cover for Pogba.
“Mourinho clearly needs one more big transfer window in the summer to bridge that gap between Man United and Man City,” Cunningham told Irish radio station Newstalk.
“He needs a solution for Pogba when he comes out of the team to ensure there isn’t a drop in performance.”
Pogba produced one of his best performances of the season in Manchester United’s 3-1 win at title rivals Arsenal in north London before he was sent off with 16 minutes to go.
The France star moved to Manchester United in an £89m deal from Serie A giants Juventus in the 2016 summer transfer window.
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