And while the 20-year-old may have the benefit of youth on his side for the quick five-day turnaround, Cullen admitted he has been careful to manage the centre - not just this week but during the season as a whole.
The Ireland Under-20 international caught the eye with his performances during last weekend's GUINNESS PRO12 clash, and Cullen will be interested to see if his player can build on that against Connacht at the RDS.
"We've tried to manage Garry in the lead-in to Christmas because he was doing exams, so he's come back in," Cullen told the Irish Examiner.
"These are a couple of games that we sort of ear-marked for him and we'll see how he goes.
"I thought he did some really, really good things against Munster. You've got the benefit of youth, so hopefully he recovers really well over the five days.
"We tried to manage him during the week like we have all four of the guys that are doubling up again with that short turnaround."
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