Penalties are a lottery. Tonight, our luck was out.
In truth, Stephen Kenny's side deserved more.
This was the best Ireland performance we have seen in some time. They kept the ball well for the majority of the game, and were far more threatening in attack without losing any of our defensive solidity.
The signs are there. Now we push forward into a new era.
Here's how we rated the performance on the night.
Ireland Player Ratings
Darren Randolph - 7
Had little in the opening quarter, pulling off a cracking save just before the interval to deny Slovakia the opening goal. It was a sight we have become very familiar with in recent years.
Was beaten in the second half only to be saved by his central defender, but Randolph was as solid as ever. He came so close on a couple of occasions in the shootout, but it just wasn't to be.
Matt Doherty - 6
Had a difficult start to the game, giving the ball away and committing some cheap fouls on a couple of occasions. His impact going forward was limited for the opening hour, but the introduction of Robbie Brady gave Doherty the room to drive up the pitch.
He looked dangerous in the closing stages of normal time as Ireland threatened but couldn't quite find the final ball. Struck the bar with his penalty, which proved to be the nail in the coffin.
Shane Duffy - 9
Wasn't tested much defensively and, with a couple of exceptions early on, Duffy seemed more assured in possession this evening.
He threatened with his aerial presence in the opposition penalty area on a few occasions and was clearly the target at every attacking set-piece. His goal-line clearance late in the second half was one of the best pieces of defending you are likely to see.
He continued to come up big at the back time and time again.
John Egan - 7
Egan had little to do in the opening period, although he did seem to be taking it upon himself to get Ireland moving the ball at times.
His contributions were not as obvious as Duffy's, but it was an excellent performance from the Sheffield United man.
Enda Stevens - 7
With the majority of the Irish play coming down the right flank, Stevens was offered few opportunities to make an impact going forward in the opening period.
Produced a stunning pass to give Alan Browne a massive opportunity, only for the Slovak goalkeeper to produce an excellent save. Stevens had more space once Robinson moved onto the left and used it well.
James McCarthy - 6
McCarthy had a partner in the holding midfield role this evening, and was the more defensively solid of the two. He got around the pitch well and put in some strong challenges.
A decent showing, but didn't quite have the impact on the ball we would have hoped for. Replaced by Alan Browne on 60 minutes after picking up a knock.
Conor Hourihane - 5
Hourihane was largely absent in the opening period, allowing the Slovakian midfield far too much time on the ball.
The Aston Villa man swung in some inviting deliveries at times, but his lack of intensity off the ball was a major concern. He grew into the game a bit more late on, coming up with some incisive forward passes, but he missed an absolute sitter which would have won the game for Ireland in normal time.
Took his penalty well.
Jeff Hendrick - 6
Playing much higher up the pitch tonight, almost acting as a second striker when Ireland were out of possession. He linked the play well at times, but also gave the ball away needlessly on occasion.
After a promising start, Hendrick seemed to drift out of the game. He was deployed in a deeper role after the first hour and did keep the ball moving well.
Callum Robinson - 8
Robinson injected some urgency into Ireland's play whenever he got on the ball, often drifting in-field. Had one or two long-range efforts that didn't really threaten.
He moved to the left flank after James McClean was substituted and continued to impress, late on laying a chance on a silver platter for Hourihane which the midfielder missed. The forward was replaced by Callum O'Dowda in extra time after running out of legs.
David McGoldrick - 9
Had very little joy in the first half, but McGoldrick continued to put in the hard yards. McGoldrick was forced to drift out of the centre forward position in search of possession.
He continued to try and make things happen, including producing an incredible mazy run to beat a number of defenders and result in the chance for Hourihane.
He was the one in the Ireland team to take the initiative with the game on the line. Withdrawn late on after working himself into the ground. A brilliant performance.
James McClean - 5
Showed he was up for this one right from the off with a lung-bursting run and vital defensive intervention inside the second minute. McClean was often the target of long diagonal balls in the opening half but they rarely came to fruition.
McClean had an excellent chance in the 37th minute but completely fluffed his lines. He worked hard in defence and attack, but things didn't come off for him.
Replaced by Robbie Brady on the hour mark.
Robbie Brady - 6
Brady made a difference after coming on, with his propensity to drift in-field leaving a huge amount of space for Matt Doherty to attack.
He looked dangerous when picking the ball up at the edge of the box and did well. Was calmness personified for his penalty.
Alan Browne - 7
Browne had Ireland's biggest chance of the game up to that point only a few moments after coming on, forcing a brilliant save from the Slovakia goalkeeper. He looked lively after coming on, filling the attacking midfield role previously occupied by Hendrick.
Had another golden opportunity in extra time only for his flick to rebound off the post. Missed his penalty.
Callum O'Dowda - 7
Made an instant impact, linking up with Brady on the right to set up Alan Browne. He certainly didn't look like a played who hadn't played in over a month, injecting some much needed energy after his introduction.
A very good showing.