Republic of Ireland boss Martin O'Neill said France's longer recovery before their Euro 2016 second-round tie was crucial as the Irish went out in Lyon.
After France came from behind to win 2-1, O'Neill said the fact the hosts had three more days' rest after their final group game was "incredible".
The Republic were back in action four days after their 1-0 win over Italy.
"A three-day differential is genuinely too much and it took its toll on us in the second half," said O'Neill.
"It will sound like an excuse and it's not meant to be. But it is incredible. It really is incredible.
"We knew at the start of the tournament when we were looking at it that after a really tough group, if we took our place in the last 16, the chances were there was going to be a big differential between us and some of the sides that we might play in the competition.
"France, it looked as if it was geared from them to win their group, which they did. Well done to them but three days is far too much. "
Early goal 'rattled' hosts
Robbie Brady's early penalty gave the Republic the lead but two second-half Antoine Griezmann goals earned France victory as the hosts took control. The tiring Irish ended with 10 men following Shane Duffy's sending-off for a trip on the goalscorer.
"We got the goal and we were pretty comfortable in the first half," added O'Neill.
"We put them under pressure. We rattled them. We got the goal and it actually settled us down. I thought that we were continuing to do very well in the game.
"It's all ifs, buts and maybes, but if we had gone another six, seven, eight minutes without conceding, there would have been a lot of pressure on France and I think we could have used that to our advantage.
"The two goals that they scored came within two or three minutes of each other. If I look back, I think the goals we have conceded have been quite poor. That's my only annoyance."
Coleman devastated as Republic exit
Republic captain Seamus Coleman's huge disappointment was there for all to see after the defeat.
"We felt like it was there for us today," said the Everton defender, 27.
"We took a lot of belief from the Italy game. In the first half we played well. The second half was always going to be tough. We just couldn't keep the door closed for long enough."
The Donegal man paid tribute to the team's fans who were restricted to fewer than 5,000 tickets at the Stade de Lyon.
"We only had a little corner of the ground but they were so loud and so positive. It's a special bond between the fans and players.
"We would have loved to have gone a bit further for them."