Jose Mourinho has admitted that Zlatan Ibrahimovic's injury was a key reason for Manchester United spending big to sign Romelu Lukaku.

The Swedish star suffered a serious knee injury in April, bringing his season to an end following a hugely successful first campaign at Old Trafford in which he scored 28 goals.

Lukaku was subsequently signed from Everton for an initial £75m earlier this month, and Mourinho said that the deal was needed to ensure the club did not go without a "strong striker" for six months.

Addressing the team's current attacking options, Mourinho told Sky Sports News: "We spent big money on a striker because, with strikers, you either spend or you don't get.

"We spent because of what happened to Zlatan and we cannot allow ourselves to be without an important, strong striker for the first six months of the season."

Ibrahimovic is undergoing his rehabilitation with United and could yet pen a new deal with the club early next year, with talks expected around Christmas time.