The Lions will take six live picks into the draft, and could open their night by adding more depth to their tall stocks, with little separating Bontempelli and McCarthy.
Bontempelli is a 193cm midfielder who wins his own possessions, marks well and is building his frame.
He shot into top 10 calculations towards the end of the season when he starred for the Northern Knights in their push to the TAC Cup finals.
Click here to watch the highlights of top 10 prospect Marcus Bontempelli
McCarthy has been regularly linked to the Lions over the past two weeks as the draft draws closer.
The leaping, marking West Australian key forward made a lasting impression at the under-18 championships when he was named an All Australian.
Meet Cameron McCarthy: Exclusive interview and draft analysis
He ended the carnival with a broken fibula and didn't play again for the season, but will be fit to start the pre-season.
McCarthy is a more conventional key forward, although Bontempelli will likely develop into a player capable of moving into more roles, having highlighted his endurance at the NAB AFL Draft Combine with a 14.7 beep test.
The pair are the wildcards of the top 10.
Bontempelli may already be taken before the Lions' selection, with Collingwood (pick six and 10) and the Western Bulldogs (pick four) considering him. The Magpies have also been raised as a possible home for McCarthy.
Collingwood's pair of selections continues to leave the draft order uncertain, although clubs believe there will be no surprise additions to the first 12 or so draft picks come next Thursday.
Melbourne has been linked strongly to speedy midfielder Nathan Freeman at pick nine and Greater Western Sydney is likely to consider small on-baller Lewis Taylor for selection 14.
The Sydney Swans appear keen to add a mature ruckman to their list, having invited Sturt big man Angus Kurtze to a day of testing on Tuesday.
The 27-year-old considered the opportunity but declined and will stick with his SANFL club where he recently played his 100th senior game.
Twitter: @AFL_CalTwomey
