Dan Leavy is happy to take it one week at a time after making his first start in 20 months.
Cullen's career was put on hold when he sustained a serious knee injury against Ulster in the Champions Cup quarter-final in March 2019, ending his hopes of representing Ireland at the World Cup in Japan.
The Covid-19 outbreak delayed his return but he has been making slow steps in recent weeks before being named in the starting XV for Monday's Guinness PRO14 clash against Edinburgh and he responded by putting in a man of the match display for the Blues, which included a well-deserved try in the 42nd minute.
Reflecting on his first start in 20 months, Leavy told eir sport: "It's great to be back. It's been a long journey, I've picked up a few 20 or 25 minutes in the last few weeks and I was just raring to go. I got the green light today and we had a great win, so I am delighted to be part of it.
"I am delighted with the performance from the team and I finally got my try."
Leavy has enjoyed a couple of brief substitute appearances for the reigning Guinness PRO14 champions and he was pleased with how his knee is feeling.
"I've done a lot of work and even last March and April I was gearing up to play before Covid hit so I've had a long time doing a lot of breakdown work with Hugh Hogan, one of our coaches, so I'm pretty well versed on it at this stage, but there is nothing quite like getting into a game and getting some proper hits on," he went on. "I loved it, I'm confident in my body and just looking for some more game time now."
Having made a successful return to provincial action, Leavy will be hoping to catch the eye of Ireland head coach Andy Farrell in the coming months, but for now he is not looking beyond next weekend's Guinness PRO14 tie against Cardiff.
“I'm just taking it week by week. We're back in the RDS in six days for Cardiff, so I'm not looking too far ahead at the moment,” he added.
See five LIVE Guinness PRO14 games this weekend, including Leinster v Cardiff (eir sport 1, Sun, Nov 22, 5.15pm)