“Sometimes in a league game you’re happy enough to get a single point out of it. But we want to win this one, particularly as it’s on our home turf.”

The Bohemian manager admitted he would prefer to be playing a league game following last week’s defeat. “It leaves a bad taste in the mouth, and we’re waiting two weeks to put things right. But this is another competition we’re hoping to do well in.

“It’s a tough ask as this is one of only two all-Premier Division ties in the round. The cup draw hasn’t been kind to either Drogheda or ourselves and it’s going to be difficult for both of us.”

Despite his team slipping down the league table, Callaghan insists they go into the cup tie confident. “I’m always confident going into a match, even when performances may not have matched the standards we set for ourselves,” he said.

“We had a good result against them up in Drogheda [2-2, four weeks ago]. They have had some problems with consistency themselves. They had a heavy defeat in the Setanta Cup final and they seem to be conceding more goals than they did last year.

“It’s probably going to be an open game and you’ll see goals. We just hope we get more than they do.”

The most recent cup encounter between the sides was in the EA Sports Cup last season (10 April 2012). That game was level, 1-1, after extra time and went to penalties, Drogheda winning the shoot-out.

For Friday, Bohs are without Dave Scully, suspended for one match with four yellow cards. Owen Heary remains out with a hip injury, though he has returned to training and may be fit for Bohemians’ next league match.

The absence of Scully and Heary, following the recent departure of Stephen Paisley, means Bohemians are short on bigger, stronger players.

“Drogheda are a strong, physical side and we may be a bit lightweight. To be missing Dave’s height and his battling qualities is disappointing,” said Callaghan.

Roberto Lopes, Luke Byrne and Chris Lyons have returned to the squad after training with the Ireland under-21s. Callaghan is delighted with the opportunity these young players have had, “and it shows we must be doing something right when we supplied three of the 22 players in the squad”.

Last Friday’s late equaliser against Shamrock Rovers represented just reward for the players’ efforts, added Callaghan. “That was probably our best performance of the season. We passed the ball well and we had a great confidence and energy about us.”

Ryan McEvoy’s equaliser also cancelled out a deficit due to “as bad a referee’s decision as I’ve seen anywhere in the game”, according to the Bohemian manager.

“To come back from that and get a goal in injury time was brilliant. But it would have been one hell of an injustice if we hadn’t got something from that game.”

Friday’s match will be Bohemians’ second league game against St Patrick’s Athletic in less than a month. “We went over to them a few weeks back and we had a good performance. They’re a very good side and it will be a difficult game in Dalymount. We will have to be at our best to get a result,” said Callaghan.

Nine of the last ten league games between Bohemians and Pats have been drawn or decided by a single goal either way.

Captain Owen Heary (hip) and Conor O’Brien (illness) are out, as is Keith Buckley who serves out the second game of his two-match suspension.

Callaghan made eight changes from last Friday to Monday. “You take a big risk when you do that but you’ve got to give these guys game-time because you will need them before the end of the season.”

Against Shamrock Rovers he put on 19-year-old defender Michael Scott for his first league appearance, placing him up-front in the hope of taking advantage of his height and he was on the field when the equaliser was scored.

Callaghan’s faith in the other less-tested players was rewarded on Monday, as was his entrusting of the captaincy to Luke Byrne, the third 19-year-old to lead Bohemians’ senior team in the last three years.

“I saw leadership qualities in Luke the first week I trained with him. Asking him to skipper the side is just reward for Luke’s attitude, effort and dedication.”

“If you get the right draws and right results you find yourself all of a sudden in a semi-final. It’s a very important game from the club’s perspective,” he added.

Looking back to Friday’s Dublin derby, Callaghan believes a draw was the least his side deserved having proved more than a match for their more illustrious opponents for large periods of the game.

Callaghan added:  “It’s chalk and cheese in terms of the personnel at the moment. We put it up to them on Friday and we fully deserved our point if not the three.

“The group that we work with, every day in training they work their socks off. Their attitude for the cause has been absolutely superb all season.

“We’ve had some tough games and we’re still a work in progress. I keep telling people I’m not trying to build a team, I’m trying to build a club and you can’t build a club overnight.

“It takes a bit of time to develop those young kids. But they’re growing in stature. Lukey Byrne I thought was absolutely brilliant on Friday alongside Dave Mulcahy, who got man of the match. You could have given it to five or six of our lads.

“Michael Scott came on for his debut. You could see the difference with what Rovers were bringing off the bench.”

With a congested fixture list, Callaghan expects “to rotate one or two players”  and his squad is boosted by the return of defender Roberto Lyons and striker Chris Lyons, who both missed Friday’s game through suspension.

But Keith Buckley – one of the star performers in Tallaght – misses out as he serves the first of a two-match ban having been sent off in last week’s 1-0 defeat against UCD.

NOTE: Members can attend this game for the reduced price of €5.

“I thought we were the better side against Cork for most of the match. Tommy Dunne [Cork City manager] said to me after the match they had got out of jail.

“Against UCD one or two contentious decisions swung the match. Those games turned on slight errors.”

Motivating the players has not been an issue but a derby match against Shamrock Rovers represents a particular challenge. “The magnitude of the game speaks for itself, given the past encounters between the sides. But I don’t do the history side of things. Every game is taken on its merits,” said Callaghan.

“Shamrock Rovers have shown what they can achieve when they’re on form. If we’re not 100 per cent on the night it’s going to be very difficult.”

Bohemians’ 1-0 win in Tallaght last September marked 19-year-old Greg Murray’s second league appearance in goal for Bohemians and, on Friday, he is likely to make his first league start this season. Dean Delany’s groin injury will probably rule him out after 13 successive league starts.

This is one of several enforced changes to the Bohemian line-up, as striker Chris Lyons and defender Roberto Lopes, both of them central to the team’s endeavours this season, are suspended.

The 3-5-2 formation used in recent games is likely to be set aside and Callaghan will consider the claims of Dwayne Wilson, Kevin Devaney and Dave Scully to start up-front or in a position just off the furthest forward.

Lopes was rested against Cork City after starting all 12 league games in the season up to that. “I knew the suspension was coming and the rest won’t do him any harm,” said his manager.

Looking forward to next Monday’s EA Sports Cup match at home to Bray Wanderers, Callaghan insisted that “the plan for the season was to win a trophy and this is a trophy we could win”.

“If you get the right draws and right results you find yourself all of a sudden in a semi-final. It’s a very important game from the club’s perspective,” he added.

The manager expects “to rotate one or two players” but is hoping that there are no injuries coming out of Friday’s match that require more changes than that.

“I thought we were very poor first half, we stood off UCD and allowed them to dictate the play. But second half I thought we were the better side, and we definitely had a couple of decisions go against us. I did have a chat with the referee after the game, and he said he didn’t see the penalty incident.”

Callaghan was pleased with the fact that referee Padraigh Sutton was open enough to talk to the Gypsies’ boss about the incidents, which also included a disallowed Kevin Devaney goal. “I had a good chat with Padraigh after the game, and it was the first time in a long time that a referee has allowed me to come in and talk to them. I think that the communication process with the referees has to improve. When you can go in and chat about a few of the incidents and they explain why they gave a particular call, it’s much more open and satisfying for me. I can air a few opinions and we can move on”.

Callaghan also called on the Gypsies’ players to keep their discipline after Keith Buckley’s late red card against the Students. “Discipline is important at any stage of the season. It’s something we stress to the lads prior to every game, you’ve got to keep your heads in certain situations. It’s hard to take some of the decisions but, in fairness to the referees, they don’t go out there to intentionally make those decisions.”

Looking ahead to Cork City on Friday, Callaghan is peering up the table rather than down — the Leesiders are just a point ahead of Bohs in the Premier Division. “They’ve assembled quite a decent squad but a couple of results have gone against them, they’ve conceded late goals here and there. We know if we win the game we go above them, which is a great incentive for the players. It was disappointing that our run came to an end, but we’ve got to get back on the bike and kick on.”

The Bohs boss also went into detail about the 3-5-2 formation implemented in the last few games, and the attacking threat that the system gives. “The thinking behind it is to create more opportunities, which I think it does. We scored three times against Bray, twice at Drogheda, and once away to St Pat’s by playing the system. What it does is throw more men forward. As with every attacking system, it does leave gaps, but we’ve been working on ways to counter-act that. The idea was to get more goals, and if we win games 3-2 I’ll be quite happy. Not only does it entertain the fans, but we can also hopefully get the three points.”

For Friday’s game Bohs will be without the suspended Keith Buckley but have no serious injury concerns. Captain Owen Heary returned to the starting line-up on Tuesday after a long lay-off, while Stephen Traynor was back on the bench following a surgical procedure.