The Republic of Ireland's defeat on penalties by Slovakia in Thursday's Euro 2020 play-off semi-final "is a harsh way to lose", says Stephen Kenny.
Slovakia won the shootout 4-2 after a goalless draw in Bratislava.
The defeat ends the Republic's dream of reaching a third successive European Championship finals.
"The stakes are high, the prize is absolutely huge and we can't get it back, and that is difficult to accept," said boss Kenny.
- Report: Slovakia beat Republic on penalties
- Second Republic of Ireland backroom member tests positive for Covid-19
- As it happened: Slovakia edge Republic in shootout
Victory for the Republic of Ireland would have set up a final with neighbours Northern Ireland at Windsor Park on 12 November.
The Republic missed several gilt-edged opportunities to book their spot in the decider, with the most notable chances falling to Conor Hourihane and Alan Browne.
Browne then saw his penalty saved by Slovak keeper Marek Rodak before Matt Doherty's miss sealed the home win.
Kenny lost forwards Adam Idah and Aaron Connolly before the game due to "stringent" Covid-19 restrictions after the pair were deemed to be in close contact with a non-playing member of staff who tested positive for coronavirus.
With the nature of the defeat and the late enforced changes to his team, Kenny added that his side "showed great qualities as men".
"We looked like we really wanted to win it and we had some good chances but we just couldn't score that goal that we needed," added Kenny, speaking to Sky Sports.
"The players didn't deserve to lose the game. Their workrate was phenomenal and their determination to win tonight and make the final was very evident.
"It was very unfortunate and a harsh way to lose but that is how it goes.
"I'm really, really disappointed for the players, they deserve better and I can't really ask any more of them."
'Defeat is heartbreaking'
Republic captain Shane Duffy said the defeat in the shootout was "hard to put it into words".
"It's never nice to lose on penalties and it is a tough one to take," said the Celtic defender.
"It's disappointing. We created chances but it didn't drop for us and it wasn't our night.
"It went the whole way and both teams cancelled each other out. It's a hard one to take at the minute and it is heartbreaking.
"Our lads were brave stepping up and we knew the pressure in the game. You've got to give them credit for taking one and we'll hopefully bounce back from this and go again."