During Tuesday night's William Hill Scottish Cup win over Motherwell, Aberdeen fans sang about wanting Ryan Fraser to stay at the club.

That seems increasingly unlikely, since several English clubs are keen on the exciting young winger, but there are other prospects at the club to value. On the same day that Fraser declined a contract extension, Joe Shaughnessy signed one that keeps him at the club until 2015.

Supporters don't often acclaim young defenders, but Shaughnessy was impressive at Fir Park. There was licence to join the attack, since Aberdeen were playing with three central defenders, but he used the opportunities effectively. It was his lay-off that led to the opening goal for Rory Fallon, then he finished decisively when he met Johnny Hayes' cross. In both instances, Shaughnessy was deep inside the Motherwell penalty area.

"As for my goal, I thought I'd take the chance," he said. "From playing at the back I know that defenders shouldn't let the ball go across your body in the box and it worked out for me. I have the legs to get up and down the pitch so when I see moves building up I like to take a chance. I had a chance earlier when I should have put the ball back across the goal but didn't. I always feel that I have a chance to get on the scoresheet if I can get in or around the box. To be honest, I didn't know what to do [to celebrate].

"When I signed my last contract for two years my main aim was to push on and get close to the first team. That's happened so, when I was offered another two years, it was an easy choice for me. I don't see many better places for me to develop as a player while getting a chance in the side. I can understand Ryan's decision but it's each to their own. He's done really well when he's come in and played so it's up to him if that's what he thinks."

Shaughnessy recognises that his career is best served by staying at Pittodrie. His manager, Craig Brown, referred to him as nice, sensible, polite young man, but there will be no room for complacency. The defender spent last year on loan at Forfar Athletic and has now broken into the first team while injuries abound. There is an opportunity to establish himself but he has to be assertive in making the most of it.

The 20-year-old Irishman is versatile, being able to play at centre-back and left-back, but is more comfortable on the right flank. He is learning by playing alongside the likes of Russell Anderson and Mark Reynolds – who was outstanding at Fir Park – while the management team of Brown and Archie Knox have spent their careers developing young talents. That has to be balanced with the competitive demands of Aberdeen's season, though. The club reached last term's Scottish Cup semi-final but lost to Hibernian, who will now be their opponents in the fifth round at Easter Road. Yet Brown's side have already defeated Hibs in Edinburgh this season.

It will irk Brown that his side has found better form away from home this season, but the defensive strength and counter-attacking outlets of Hayes and Niall McGinn suit the circumstances of playing on the road. A quiet sense of self-belief has begun to assert itself among the Aberdeen players, though, and there is a conviction that the team might achieve something significant this season.

"The next round will be another tough tie away from home," said Shaughnessy. "There's definitely a good feeling about this competition this year – there's a good feeling around the club in general. We're doing a lot better in the league than we have done in previous seasons and I don't see any reason why we can't go all the way in the cup.

"I don't know why our results away from home have been better because we haven't been performing that badly at Pittodrie, but we do feel quite comfortable on the road and we have a great travelling support. Counter-attacking is one of our strengths, with the pace the lads up front have, and we're also quite strong at the back so I suppose playing away from home suits us – and Hampden would count as being away from home."

Shaughnessy was playing for Forfar while Aberdeen were contesting last season's Scottish Cup semi-final at Hampden, but he is just as committed as the rest of the players to go one stage further. "We now have a chance to put those wrongs right," he said. "It would be nice for the fans to finally get a win at Hampden."