While the Blues have already named two newcomers in Sam Petrevski-Seton and Jarrod Pickett, tall defender Macreadie, named as an emergency, may be a late inclusion as Carlton ponder whether to start regular backman Jacob Weitering up forward.

Macreadie, 18, a GWS Academy player who Carlton picked up at No.47 in last year's national draft, played in two of the Blues' JLT series games, impressing on St Kilda key forward Josh Bruce and, for a shorter time, opposed to Fremantle's Cam McCarthy.

If he is picked to make his debut, Jed Lamb, named on the interchange bench, is the man most likely to make way.

The last-minute selection intrigue comes as Carlton ponder going with a taller forward set-up against the Tigers. Macreadie would provide cover for the Blues down back should coach Brendon Bolton elect to play Weitering forward.

Bolton was cagey about that possibility on Wednesday. "I'm going to hold that one really close to my chest," he said. "You'll probably see him at both ends, but I'm not going to let you know where he starts. I'm going to have to keep Richmond guessing."