As first revealed earlier this week before the Manchester City fixture, forward Guessand is close to returning from an injury that has sidelined him since the Fiorentina quarter-final first leg win.
However, Borna Sosa may have to wait for the final Premier League game against Arsenal before he is available again.
It means Glasner's squad are close to a clean bill of health ahead of the final three games of the season. Only long-term absentees Eddie Nketiah and Cheick Doucouré remain unavailable, while the Manager also revealed there is still a question mark over Sosa's return.
Ahead of the trip to Brentford, the Palace Manager said: "We are training later today for the first time [since the City game], so we'll need to see.
"But we hope that Evann Guessand returns to the squad on Sunday. It's looking good, but he has two training sessions to come through.
"We want him getting a few minutes, so he can be an option in Leipzig.
"Borna Sosa's situation is a bit more questionable, he might still be out until Arsenal. But all others are available."
Match details
Brentford v Crystal Palace
- Sunday, 17th May
- 15:00 BST
- Gtech Community Stadium
- Premier League
- Live on Palace TV+