I'd hate to play my debut game in front of 70k+ at the G if it was my job to shut down Chris Yarran on live national tv! Seems like too much for a first gamer. I don't think Lambert has the leg-speed for that job anyway.
I'd give Titch first shot at Yarran to match him for speed & agility, even if it takes away an attacking option. Malthouse would love to see us put a defensive plodder on Yarran, that would just be the signal for Yarran to run & carry all night!
I can see Lambert playing as a small forward & second line midfielder, but I can't see him matching it with Yarran in a foot race.