After the season-ending injury to rebounding defender Jackson Thurlow, mature-aged rookie Tom Ruggles has put himself in the frame with two solid NAB Challenge performances against Essendon and Fremantle.

With 38 players on their primary list, the Cats don't have to wait for a long-term injury to promote a rookie although they may still put Thurlow on the long-term injury list.

Ruggles, 23, knows the Cats' system and is big enough to cope with the game's demands although it would be a big call to throw him into senior football on Easter Monday against Hawthorn.

Next in line is first-year player Jock Cornell but he will be given time, while Zac Bates has pace and is smart but he has several small forwards ahead of him at this stage.

Defender Cam Delaney has been battling injury, while young ruckmen Tom Read and Padraig Lucey are still developing.

Which rookie should be elevated to the Cats senior list? Have your say in our poll below.