Former Dundee United centre-back Gavin Gunning is add- ed following a hamstring injury as are the defence -minded Lee Kilday and Ricki Lamie who played for the Greenock side’s under-20 outfit during the week after knocks.
Duffy said: “Having the three players available again gives me options and I will have to take a risk with at least one of them to play against Aberdeen. We had a re-jigged defence against Queen of the South last weekend and did really well in winning 5-0 but Aberdeen are at a different level and we need to have defenders in defence.”
Winger Caolan McAleer is also available after a knock, but Conor Pepper and Michael Tidser remain out injured and the team’s star man, Ross Forbes, is missing through suspension.
Duffy, pictured, said: “Ross scored last weekend and was involved in the four other goals so he will be missed. He has been different class this season and is at the heart of the set-pieces that we take as well as carrying a goal threat on his own.
“He will be a huge loss but one we just have to deal with.”
The Cappielow men are heading to Hampden with their tails up after their rousing Dumfries success last weekend. Duffy added: “The feelgood effect from that win has made training really enjoyable this week. The boys have been laughing and joking as opposed to being concerned about facing a really good Aberdeen side.
“We have been able to enjoy the build-up which has involved a lot more tactical work than we do for Championship games.”
The match is Morton’s first semi-final in a major competition for 35 years but Duffy hopes that his crop of players will not have to wait so long for their next taste of the big-match atmosphere.
“I hope for my players’ sake this isn’t a once-in-a-career occasion,” he said. “I want it to be the first of many for them.
“We’ve got a young side. I can say they are good enough and they can believe it themselves.
“But ultimately we won’t know until they are in amongst it.
“Before then you have no idea how they will cope with the expectation that’s on them, how they cope with the spotlight.
“For a lot of them this is the first time around, while Aberdeen have all the experience having been in the final and a few semis over the last few years.”