Celtic have competed in multiple competitions this season, and the gruelling schedule is starting to catch up with them.
The Bhoys have had to compete in Europe as well as three domestic competitions, and the regular fixtures are starting to catch up with the squad.
Deila says that Celtic are starting to show signs of tiredness now, but he is demanding that his side keep going to ensure that they win the title.
"It looks now that some of the players are starting to feel it after we've played 57 games this season," he said.
"That's normal. But they just have to stick in there and win games. We have shown a lot of consistency in the last month, in terms of winning games, and that is satisfying."
Thankfully for Celtic, they have already done most of their hard work this season and the fatigue the squad are feeling shouldn't adversely impact on their chances of success too much.
The Bhoys are currently eight points clear of Aberdeen at the top of the Scottish Premiership table, and that looks to be an unassailable advantage.
It means that Celtic can look back at this season with a lot of pride. Although they didn't manage to secure the treble, they appear set to claim the double and that is an encouraging start for Deila during his first year in charge.
The challenge for Deila will be to build on these foundations next season, and he will be hoping that he can make the necessary additions to allow him to rotate more next term to ensure that his side stay fresh for the duration of the campaign.