James Mortimer 01.Aug.2012Getty Images
The Chiefs lock further strained his medial ligament on his right knee towards the end of match against the Crusaders, and while the injury can have a recovery period of six to eight weeks - it is a complaint that can be overcome via the pain barrier.
Chiefs coach Dave Rennie told allblacks.com that the goal was simply to get Clarke to the level he was before last Friday's Semi-Final.
"He's still 50/50" Rennie said.
"If it wasn't a final we wouldn't be considering him, but we are taking it day by day to make sure Craig can play."
Clarke himself has said that he will take the field even if in pain, and Rennie said that could be the case if he comes through basic medical tests.
"We might have to put some extra strapping on there and get some painkillers in so he can take the field," the Chiefs coach said.
"This injury can typically take up to eight weeks to heal, so we're also being careful."
The Chiefs had an open training session yesterday, and are scheduled to have a light day today, before taking part in a final training session that will end with the team naming on Thursday.
Clarke will need to prove his knee can stand up to running, and hope that the swelling continues to subside over the next 24-48 hours.
If Clarke was ruled out, there was consideration that number eight Kane Thompson may shift to the second row, with the Samoan international having experience there, while Mike Fitzgerald was another option.
If Thompson plays at lock, Messam would likely shift to number eight.