Manchester United expect Zlatan Ibrahimovic to sign a new contract to stay at Old Trafford as early as this week, sources have told ESPN FC.

Free agent Ibrahimovic, 35, is recovering from a knee ligament injury sustained in a Europa League match against Anderlecht in April which was expected to keep him out until 2018.

The new contract will be announced earlier than anticipated due to the former Sweden international's quick recovery.

From the moment he suffered his injury against Anderlecht, it was established that Ibrahimovic would do his rehabilitation at United's AON Training Centre, even though he was due to be out of contract in June.

United boss Jose Mourinho has wanted him to sign a contract to stay at the club all along. The pair get on well and Mourinho was hugely impressed not only by Ibrahimovic's 28 goals in his first season, but his influence in a dressing room lacking big characters.

Zlatan Ibrahimovic's Manchester United contract expired in June. Alex Broadway - The FA/The FA via Getty Images

United's commercial department will receive a boost from the new contract, given shirts with Ibrahimovic's name on the back outsold any other player by at least two to one last season.

Ibrahimovic scored 17 times in 27 Premier League starts, racking up 28 goals overall. Marcus Rashford and Henrikh Mkhitaryan, United's next highest scorers, managed 11 each.

LA Galaxy were understood to be keen to sign the striker in July, but he would prefer to return to United, even though his wage will be significantly lower than it was in the one-year deal he signed with the Red Devils after joining on a free transfer from Paris Saint-Germain in June 2016.

Romelu Lukaku is now considered United's main striker, with Rashford and Anthony Martial both starting the season well in a rapid United attack which has scored eight goals in their opening two Premier League games.

Yet Ibrahimovic's goals, experience, personality and winning drive, plus the potential impact of a player still considered one of the best finishers in football, could be significant as United aim to compete for trophies on four fronts this season.