The 28-year-old has been sidelined for the past six months with a knee problem but made his first appearance of the season as a substitute against Blackburn at the weekend before getting 70 minutes under his belt for the reserves on Tuesday.
Cook now has to try to earn a place in Warnock's table-topping side on a regular basis.
"The knee felt good and I was really pleased with that, there was no pain at all," he said.
"I am probably going to need another two or three reserve matches and then take things from there. The aim is to be in and around the squad and hopefully in a month or two work my way into the team.
"I know I've got to impress the manager when I get the chance. It's down to me to put it into his mind that I am worthy of a start."
Source: PA
Source: PA