Concussion protocol meant Lerma had to miss the games against Aston Villa and Macclesfield, after he was substituted with a head injury in the first-half of our last trip to north-east, against Newcastle. But he is set to play at the Stadium of Light.
Danny Imray, who has returned from his loan spell at Blackpool, could also feature against Sunderland.
"Jefferson Lerma can play again tomorrow," Glasner said.
"Dani [Muñoz] has had one training session so far this week. He will train with us next week and should be avaialable against Chelsea, the same with Ismaïla Sarr [following AFCON]. This will give us more options again.
"Danny Imray has been called back and he will be in the squad tomorrow. Right now the number of players is quite short."
A further positive update came around defender Chadi Riad, who will be also be included in the group that travels up to Sunderland.
He last featured in a matchday squad almost exactly a year ago to the day, when he was on the bench for a 2-0 win at West Ham United.
"He [Riad] has been out for one year," added Glasner. "And he was going up to Nottingham to play on Friday night [for the Under-21s], but he will be in the matchday squad tomorrow, after one year.
"Sometimes things come quicker than expected. He has had one full training week with us and 45 minutes [with the U21s], but did really well this week."
The manager also confirmed Marc Guéhi wouldn't feature in tomorrow's game: "Marc doesn’t play tomorrow for us."
Match Details
Sunderland v Crystal Palace
- Saturday, 17th January
- 15:00 GMT
- Premier League
- Stadium of Light
- Live audio commentary on Palace TV+.