The 27-year old Australian topped âBoroâs scoring list with 14 goals in 36 appearances in all competitions but there is a chance that he could be on his way out of the Riverside Stadium after arriving in February 2010.
âIf another club was to ring up with an offer for Scott then it would have to be considered,â Mowbray told the Evening Gazette.
âItâs the same situation for most of our players.
âBut we havenât received any offers for Scott and we have to work on the assumption that what we have got is what we will have.
âIf that situation changes, then we will react accordingly.â
But Mowbray said that if McDonald was to remain on Teesside then he certainly would still be one of the clubâs key players.
âHe is a committed player. Thereâs no doubt that he will score a lot of goals for us next year,â he added.
âScottâs goals were important to us last season, but the main thing that impressed me was his work rate.
âWe asked him to do a job for us and he gave it everything he had got. He did a good job for the team.â
Mowbray added: âScott has gone away for the summer but he is loving his football here and he will be ready for next season.
âHe could be playing for the Australian national team next month which will help to keep him sharp. But heâs one of those players who doesnât like to take any time off.â