Shelbourne and Shamrock Rovers face crunch matches in the UEFA Conference League league phase as they go in search of their first victories of the campaign.
Here is all you need to know about the games.
TV
Both matches will be live on Premier Sport 1 and TNT Sports 4.
ONLINE
There will be a live blog on RTÉ.ie and the RTÉ News app with updates from both matches.
AVOIDING A GREEK TRAGEDY
Shamrock Rovers are up first with the 5.45pm kick-off in Athens.
After already facing some difficult games, it's not getting any easier for the Hoops.
The FAI Cup final on Sunday is the most important matter of the week for Stephen Bradley's side, despite needing points in the Europe.
That will play into his team selection. Bradley rotated his team for the game with Sparta Prague then Cup semi-finals were on the horizon. Achieving a double, one of the few things he has not accomplished in his time in Tallaght, is undoubtedly a priority.
In truth, even a first-choice Hoops side are going to find it tricky.
AEK hit six goals against Aberdeen in their last contest and sit just behind PAOK and Olympiacos in their league with nine games played.
Interestingly, they did lose to Celje, so a win is also important for the home side.
AEK have some recognisable names in their side. Luka Jovic joined Real Madrid for over €55m six years ago and has now found himself in Greece.
Marko Grujic, formerly of Liverpool, is also on their books.
PAOK have been a familiar opponent for LOI sides in recent years, including for the Hoops, but this is a first Irish clash for AEK at the OPAP Arena.
Irish fans will be familiar with the venue as it played home to Greece's 2-1 win over Ireland in the Stephen Kenny era.
SHELS IN LAST CHANCE SALOON
Shelbourne face a slightly different scenario.
It feels they let a massive opportunity go by in losing to KF Shkendija with a last-minute goal.
Now, they simple have to get three points against Kosovan side Drita if they are advance to a play-off.
Seven points is the rough estimate of what is needed.
AK Alkmaar (a), Crystal Palace (h) and Celje (a) are the final matches for Shels.
So they will need to win tonight and then try to overcome the odds, most realistically in Netherlands or Slovenia.
Defeat tonight would turn mouth-watering fixtures into dead rubbers.
Drita have been competitive in their two matches so far.
They left Finland with a 1-1 draw against KuPS, while at home had a 1-1 draw against Omonia Nicosia of Cyprus.
Like Shelbourne, their tougher matches are at the end of the campaign so they will be just as desperate for the win.
WHAT THEY SAY
O'Brien feels Shelbourne must be wary of counter attacks: "They [Drita] didn't have a lot of possession, but had a real threat on the break and created the better chances and they are probably unlucky to only have two points.
"I’m sure they’re seeing it as an opportunity for themselves to come over here and get a win. It’s going to be a tough game.
"They have some really good, highly technical players with pace in transition. I’m sure they’re going to cause us problems.
"But from my point of view as a coach, it’s about setting us up to go out and attack them. Ultimately, take our chances. Be more clinical around the final third. The last little bit of execution let us down [against Shkendija].
Meanwhile Bradley knows Shamrock Rovers are up against it in Greece: "You can tell they're a really good team, that’s quite clear.
"They’ve got real quality but we’ve shown a number of times throughout the years that when we’re at our levels, we’re a match for anyone. But we know we have to be right at it on Thursday, as we’re playing against a really good team at their home in what will be an intimidating atmosphere.
"They get big crowds, but it’s something we’re used to and it’s a great challenge to meet head-on and we’re looking forward to it."
TEAM NEWS
Shels have no new concerns.
Danny Grant is fit for Shamrock Rovers after coming on as a substitute in the final league game. Danny Mandroiu and Josh Honohan should be fit but Aaron Greene remains out .
Listen to the RTÉ Soccer podcast on Apple Podcasts, Spotify or wherever you get your podcasts.
Watch the Sports Direct FAI Cup final, Shamrock Rovers v Cork City, on Sunday from 2pm on RTÉ2 and RTÉ Player. Follow a live blog on the RTÉ News App and on rte.ie/sport. Listen to live commentary on Sunday Sport on RTÉ Radio 1
