The Red Devils are in second place in the Premier League table but 16 points adrift of runaway leaders Manchester City.
Manchester United have scored 28 goals less than the Citizens to highlight the gap between the two Manchester clubs.
Jose Mourinho has been tasked with restoring Manchester United to the pinnacle of English football following a five-year title drought.
The 20-time English champions have won the Europa League and the League Cup under Mourinho, but the manager’s style of play has attracted criticism.
Manchester United signed Chile international Alexis Sanchez in a swap deal from Arsenal in the January transfer window.
Former Red Devils winger Kanchelskis believes Manchester United need more attacking players in the summer to improve their chances of winning the Premier League title next term.
Asked who will finish higher next season, Kanchelskis told BetStars:
“It depends – if Manchester United buy new players, more attacking players with a new system of playing, they may finish higher.
“Manchester City are a stronger team who play better football now.
“If next season after the World Cup Manchester United buy new, fresh, quality players then they could be champions.”
Manchester United finished in sixth place in the Premier League table last term but are on course to end up in second spot in the table this season.
The Red Devils suffered a 2-1 loss to Spanish side Sevilla in the Champions League round of 16 last month.
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