The Red Devils' boss has admitted that the German champion retains a "strong" interest in the Poland forward and could usurp the Man Utd in the race to sign him.
Ferguson has long been an admirer of Lewandowski and Dortmund sporting director Michael Zorc has already admitted the striker could leave the club this summer. The United boss is wary of the German champion’s interest in the Poland international, although he believes the situation could change once his side is confirmed as Premier League champion -- something that could happen as soon as Monday.
Regarding his interest in Lewandowski, Ferguson told reporters: "Yeah, but Bayern Munich are strong with that too. We just have to wait and see where we are in terms of if we win the league. Then it may be different."
Ferguson also suggested that signing the Dortmund forward may complicate matters at Old Trafford, with his squad already containing several competitive forwards.
"Big signings? You are normally talking about forwards but it's complicated enough as it is with the forwards I've got,” Ferguson said.
Lewandowski has scored 31 goals in all competitions for Dortmund this season, with six of them coming during his side’s run to the Champions League semifinals.