The 27-year-old, whose current contract runs until May 2018, took his tally to 10 goals this term with a double against Ayr United at Somerset Park on Saturday to add to his 16 directs assists.
Prior to this term, former Dunfermline man Forbes had netted six times over the course of 61 appearances in his season and a half since his switch from the Pars.
Although the Ton boss considers Forbes’ contribution to have been hugely significant in both the League One title-winning campaign and the respectable return to the Championship last year, he believes the playmaker has taken his game to another level now.
Speaking exclusively to gmfc.net, Duffy said: “Ross has added a different dimension to his game because of the goals, but I think since the time he has come to the club, he has been outstanding.
“The promotion-winning season he was outstanding; last year, he had another terrific season, and this year he has gone up another level. He’s playing with a smile on his face and he’s enjoying his football. He’s really important to how we play.”
Image: David Bell