Shamrock Rovers will be without key midfielders Marc Kenny and Derek Tracey for Thursday night's UEFA Cup qualifier against top Swedish side Djurgardens.
Kenny is paying the price for being sent off in an Intertoto Cup first-round tie against Turkish club Altay Spor four years ago and now starts a three-match ban.
Manager Liam Buckley also rates Tracey "very doubtful" for the first-round first leg clash at Tolka Park due to an Achilles tendon problem.
To add to Rovers` problems, striker Tony Grant is scheduled to have a late fitness test on a thigh injury picked up in Sunday's scoreless draw with UCD in the Premier Division.
In the absence of Kenny and Tracey, the experienced Jason Colwell and Greg Costello are expected to be handed the midfield roles.
With just one point from their last four league games, Rovers know they will have to move up a gear if they are to cause problems for the in-form Djurgardens.
Manager Buckley was on a spying mission in Stockholm at the weekend, watching Djurgardens defeat AIK Gothenborg 3-0 in front of 30,000 fans.
Buckley said: "The Swedish league is of a high standard and Djurgardens are obviously a very good side.
"It's a big game for us and I have told the players to fulfil the expectations of themselves, Shamrock Rovers, our fans and the National League."
Buckley believes that home support will be vital if Rovers to have anything more than an academic interest in the second leg in a fortnight's time.
"Djurgardens will bring over as many as 2,000 fans to Dublin," he said.
"We all want National League clubs to do well in Europe. Whether it's Bohemians, Shelbourne, St Patrick's Athletic or Shamrock Rovers it is good for our league if our clubs can win.
"That's why I am eager for us to have a big following on the night and the right result to take to Stockholm".
First Division side Dundalk face a monumental task to reach the next round as they travel to Croatia to tackle Varteks, conquerors of Aston Villa last season.
Manager Martin Murray will give late fitness tests to defenders Robbie Brunton (thigh) and Noel Melvin (Knee) before naming his side but defender Donal Broughan is definitely out suspended.
Former Huddersfield player Gary Haylock, a veteran of 28 previous matches in Europe with Linfield, Portadown, Panionios and Shelbourne, looks likely to lead the attack despite carrying a knock.
Murray said: "Tommy McConville, a key member of my backroom staff, has had a look at the Croatians.
"What we know is that they lost their first two games of the season before beating Osiek at the weekend, but we are probably as much in they dark about them as they are about us."
While likely to play Haylock as a lone striker, Murray will encourage midfield men Martin Reilly, Chris Lawless and David Ward to push forward at every opportunity in the hope of keeping the tie alive for the second leg at Tolka Park in a fortnight's time.