MICK McCarthy has stoked the FA Cup fires ahead of today's fifth round showdown at the Stadium of Light by insisting that Premier League high-flyers Birmingham are the underdogs.

Despite there being 17 places between the sides, the manager of Nationwide League Sunderland is adamant that his club are bigger.

Birmingham sit in ninth spot in the Premier League, three points behind fourth-placed Liverpool with a game in hand.

But McCarthy says the Black Cats can never be considered as underdogs at home - no matter who they play.

The former Republic of Ireland manager refuses to see Sunderland as anything but a Premiership club in waiting, and as big as any in the top flight.

The BBC cameras will be at the fifth round tie at the Stadium of Light believing an upset is on the cards, but McCarthy believes the upset would be a win for Steve Bruce's side.

McCarthy said: "I don't think it will be giant-killing act if we win. Giant-killing is all about the clubs not the teams. When people talk of underdogs they are normally talking about the size of a club.

"With the two clubs (Sunderland and Birmingham) it's the other way round.

"Sunderland are a massive club and when they play at home they can never be considered as underdogs.

"When you look at the teams it's different, but when you talk about giant-killing you refer to the size of the clubs, and ours is as big as any club."

McCarthy readily admits his side can't match the Blues on the pitch at present, and is hoping to use the game as a yardstick to measure their Premier League potential.

With promotion the one and only priority for the club, McCarthy rates qualifying for the FA Cup quarter-finals as a poor second.

But he won't be tempted into fielding a second XI today, insisting the players will give their all for the cause.

"Should I stick the reserves out against Birmingham City in the fifth round of the FA Cup?" asked McCarthy.

"I've only done that once. It was against Huddersfield in the Carling Cup because I thought the team I put out could still beat them - we didn't.

"If the choice is the Premier League or the quarter-finals of the Cup then it's the League.

"But it doesn't mean to say we are not going to try to win.

"You don't have the choice of a place in the play-offs or a good Cup run, but if you do it has to be the play-offs.

"There could be ifs, buts or maybes all the way through. But with the club that we've got and everything else - the supporters, training ground, infrastructure - to be a successful club, we have to be in the Premier League.

"If there's a choice between having that chance at the end of the season in a play-off or being in a quarter-final, it has to be being in the play-offs.

"But that doesn't mean to say we're not going to try to win."

McCarthy is an admirer of the work done by Tyneside-born Steve Bruce at St Andrews, with the former Manchester United stalwart moulding a Blues side difficult to break down.

But McCarthy is also well aware of their attacking threat, having watched Birmingham put three past Everton in midweek.

He said: "We're playing a good solid Premier League outfit. They are well organised and defensively sound.

"They have some good attacking players in Stan Lazaridis, Clinton Morrison, Stern John and Mikael Forssell. It's a stiff test for us.

"There's a few lads at Birmingham I know - Kenny Cunningham, Morrison and Jeff Kenna.

"Steve Bruce has done an excellent job getting them promoted when he did.

"The true test is staying in the Premier League and he's doing that. He's been backed by his club."

One player standing in the way of Sunderland's bid to reach the last eight for the first time since 1992 - the year they went all the way to Wembley only to be beaten by Liverpool - is former target Morrison.

McCarthy is very much an admirer of the ex-Crystal Palace striker, having brought him into the international fold when he was in charge at Ireland.

Morrison was keen to work under McCarthy again late last year when he was out of favour at St Andrews, and stated his interest in a loan move to Wearside.

The deal fell through, but McCarthy is still hoping the striker can be as good as his word back in November.

McCarthy said: "I think Clinton said he wanted to come and score the goals that fired Sunderland to success.

"I only hope he scores for us tomorrow."

With new signing Darren Byfield Cup-tied, McCarthy is likely to turn to Marcus Stewart, who scored at Watford last week, to partner Kevin Kyle in attack.

Fit-again Gary Breen is also likely to return in place of Joachim Bjorklund in defence.

* Former Sunderland manager Peter Reid will be at the Stadium of Light today as part of the BBC commentary team.

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