The in-form Blues finisher remains in a race against time to feature again this Super Rugby season, but his projected recovery leaves him well in the hunt for a return to the All Blacks in July.
Clarke cut an emotional figureafter injuring his hamstring during the second half of the Blues' late 21-19 win against the Brumbies in Canberra on Saturday night – a victory that equalled the franchise record 12-match winning run and secured pole position for the playoffs with one round remaining.
While Clarke is certain to be sidelined from this week's final round trip to Sydney to face the Waratahs, and the home quarter-final at Eden Park to follow, his initial three-to-four-week prognosis gives him a chance to return the deeper the Blues progress in the finals.
"That's what we're looking at for the moment," Blues assistant coach Daniel Halangahu said of Clarke's return timeframe. "He's not available this week. Beyond that, with the size of his legs, maybe they heal faster than others."
Clarke's absence is a significant blow. The 23-year-old has been a weapon on the left wing for the Blues this season – his involvement, power, angled runs, offloads and aerial prowess all coming to the fore to propel him back into All Blacks reckoning for the July series against Ireland.
"It is bad timing, especially the way he is playing and the way he started that match," Halangahu said. "He's an important part of what we're doing. We feel for him. Injuries are a horrible part of the game.
"How he pulls up by the end of this week will be important to see if it's as bad as some hamstrings are.
"We're fortunate there's some other guys who have been working really hard who are ready to go."
Blues winger Caleb Clarke in action against the Brumbies before going down with a hamstring injury. Photo / Photosport
That depth in the outside backs no longer extends to Tanielu Telea, who replaced Clarke in Canberra, after he suffered a season-ending knee injury in the same match.
"It looks like a long-term ACL type injury which is not good for him. He's been working really hard at his game."
Despite those deflections the Blues have ample cover with veteran Bryce Heem, AJ Lam and Jacob Ratumaitavuki-Kneepkens all capable of slotting on the left edge.
"Bryce was a winger until he started playing really well in the midfield so he's an option there. AJ was player of the day last time he started so he's certainly ready to go. The form Caleb was in he demanded to be in that starting position but it allows other guys to put their hand up."
The Blues confront something of a doubled-edged selection scenario this week. Having locked up top spot, they have the luxury of resting influential personnel, potentially the likes of Beauden Barrett, Dalton Papalii, Finlay Christie and Kurt Eklund, among others.
They are, however, intent on maintaining momentum before the playoffs. Claiming the franchise-record winning run outright would be fitting, too.
Akira and Rieko Ioane and Josh Goodhue are in line to return while Tom Robinson will be pushing for inclusion after missing out last week following a knock in training.
Beauden Barrett and the Blues celebrate their win over the Brumbies. Photo / Photosport
The Waratahs offer the chance for the Blues to give those who need it game time but the message from the top is clear – don't let up now.
"That temptation [to rotate] is there," Halangahu confirmed. "We're fortunate a couple of other bodies are coming through injuries – guys like Akira hopefully he comes through the week and is available and Josh Goodhue, who was probably our form player before he broke his thumb.
"Leon [MacDonald] does a phenomenal job of keeping focus on what's in front of us so we're going to Sydney and we're going to win. That's been the strongest message around here today.
"There's always something to play for. A big part of this season has been getting people proud of what we've been doing.
"We haven't really spoken about the quarter-final. We're focused on the Waratahs, my old team. Going there and getting a win is high on our priorities."
Clarke's injury aside, the Blues could not be better placed for a tilt at the inaugural title. While the Brumbies' suffocating defensive pressure exposed vulnerabilities last week, the ability to regroup and respond at the death showcased the hallmarks any championship-winning team needs.
"The last play epitomised where we feel we're at; not everything is perfect but there's a composure and a sense of everyone having a laser focus on their job at every moment. Dalton won us the ball back towards the end and no one else tried to become the hero and come up with a miracle play. At the same time, no one went into their shell to be conservative. We had a great balance of everyone being focused and calm.
"Beauden gets the plaudits but there's a lot of good things in that play, and we're seeing that every day. Finishing first on the table is one thing but we keep our feet on the ground and keep working."
