He turned to training Monday morning after more than a month on the sidelines with an ankle injury.
Krul is now pushing to reclaim his place for the trip to Chelsea at Stamford Bridge.
Caretaker boss John Carver said: “It’s good news. No disrespect to Jak Alnwick, but he has been a miss.”
Krul’s last game was the 1-0 win over Queens Park Rangers before he was injured a few days after the game.
