A win over Lithuania at Vilnius on Wednesday will almost certainly qualify the Republic of Ireland to take part in the play-offs for teams finishing second in their groups.

This is the inviting challenge awaiting Mick McCarthy's team after their 4-2 success in Iceland on Saturday, when two players, Mark Kennedy and Larus Orri Sigurdsson, were sent off in an error-strewn game.

In the event of Ireland beating Lithuania and losing their last qualifying game to Romania at Lansdowne Road on October 11th, Ireland will still be overwhelming favourites to go through on superior goal difference, irrespective of how Lithuania fare in their last game in Macedonia on the same date.

Ireland have scored 19 goals and conceded only six, so far, for a rating of plus 13, 10 better than the Lithuanians, who, to this point, have scored eight goals and conceded five.

The relevant rule reads: "If in the league system, the group matches do not result in a decision as to which team(s) qualifies for the next round of the preliminary competition, or, for the final competition, the following shall decide in this order (a) the goal difference; (b) the number of goals scored; (c) the goal difference from matches played between teams equal in points; (d) a playoff on neutral ground.

Should Wednesday's game in Vilnius be drawn, everything would then hinge on the results in the final series of games, fulfilling Mick McCarthy's earlier predictions that the process would go down to the wire.

"Obviously, I hope to win on Wednesday; but what we simply cannot afford is to lose," he said.

"Although it would still be mathematically possible for us to qualify, a Lithuanian win on Wednesday would give them all the advantages going into their last game.

"It's tight, desperately tight, but after dropping those home points to Iceland and Lithuania, it was always on the cards that we would struggle to get in.

"There are so many permutations still on the table, that it would be unwise to be dogmatic; but I think the bottom line is that we need to win here this week."

Some of the 500 Irish fans who watched the game in Iceland, have already returned home; but the expectation is that they will be replaced here by others travelling from southern Europe.

An FAI spokesman said there had been a number of inquiries from people hoping to attend the game and he confirmed that the availability of match tickets would not be a problem.

Two members of the under-21 team, Neale Fenn and Gareth Farrelly have been placed on standby for the make-or-break game in Vilnius.

This follows the escalating problems in the camp in the wake of Saturday's punitive game against Iceland where no fewer than three players - Andy Townsend, Jeff Kenna and Mark Kennedy - were carded by the referee.

Townsend and Kenna will miss one game as this was their second yellow-card offence, while Kennedy, sent off for two yellow cards in Saturday's game, could well be looking at an even heavier sentence.

The manager also confirmed yesterday that he is awaiting fitness reports from Ray Houghton (Reading) and Liam O'Brien (Tranmere) before deciding whether to ask them to travel out to Vilnius to join the squad tomorrow.

O'Brien hasn't appeared in the national team since the summer tour of the United States last year, but Houghton was an original choice for Saturday's game in Iceland before a thigh strain forced him to withdraw. Farrelly, transferred to Everton from Aston Villa during the close season, also appeared in some of McCarthy's initial selections, but Fenn, one of Tottenham's emerging stars, has yet to be cast at senior level.

Fenn was sent off in last Friday's European under-21 championship game in Iceland, but the automatic suspension which follows will, remarkably, not apply to senior competition. Townsend, after initially indicating that he would stay on in Lithuania to watch Wednesday's game, has now decided to return to England for further treatment of the leg wound which required eight stitches after Wednesday's game.