The 25-year-old marked his return from a hamstring injury with a stunning solo try as Leinster cemented their place at the top of Guinness Pro12.
There is also the small matter of a European Champions Cup semi-final at Clermont Auvergne on the horizon, and Cronin is determined to lead the charge for honours.
He said: “It was good hands and good execution for my try, I’ve been out for a few months injured so it was good to test out the leg and see if it still works properly. It was great to get a score and contribute and just be back out on the pitch playing.
Cronin had not played since his injury against Zebre in January, but looked like he had never been away when he turned on the gas to round Dan Biggar to pull his side back into the match after Sam Davies’ early score.
Dan Leavy crossed after the break to put Leinster in control, but Wales flanker Justin Tipuric barged over from close-range to edge the Ospreys back in-front.
Ross Byrne came on for Joey Carbery and landed a last minute drop-goal to all but seal victory. However, there was another turn as Byrne gave away a penalty for a high tackle on Dan Evans. British and Irish Lions hopeful Dan Biggar looked certain to land the penalty to snatch a win, but his kick drifted wide.
Leinster now look certain to advance to a home semi-final after this win put them nine points ahead of third-placed Ospreys.
Leo Cullen’s men face Pro12 champions Connacht next week before the focus switches back to Europe. If they are to claim a fourth Champions Cup title, they will have to beat French heavyweights Clermont Auvergne on French soil.
But Cronin believes Leinster have the firepower to overcome a familiar foe and make it to the Murrayfield final.
He said: “It’s going to be a huge challenge going down to Clermont, we know their forwards coach, Jono Gibbes pretty well and he will know us well too.
“I was lucky enough to be involved a few years ago down in Bordeaux when we played them and got a win, that was one of the best games I’ve been involved with.
And Cronin believes their squad depth will prove crucial in the hunt for domestic and European titles.
He said: “There were a couple of guys who came in who weren’t involved in that massive win against Wasps last week. I was playing for the A’s last week in-front of 55 people while the lads were playing at the Aviva in-front of 55,000. I was just happy to get back fit.
Davies; Giles, Fonotia, Matavesi, Evans; Biggar, Webb (c); Smith, Baldwin, Mujati, Ashley, Thornton, Cracknell, Tipuric, Baker.
S Otten for Baldwin (56), P James for Smith (69), M Fia for Mujati (58), B Davies for Ashley (56), T Ardron for Thornton (46), S Underhill for Cracknell (40), Spratt for Fonotia (67).
Nacewa; O’Loughlin, Kirchner, Henshaw, McFadden; Carbery, Gibson-Park; McGrath, Cronin, Furlong, Toner, Kearney, Ruddock, van der Flier, Conan.
J Tracey for Cronin (56), P Dooley for McGrath (56), M Ross for T Furlong (67), I Nagle for M Kearney (56), D Leavy for Conan (40),
D Kearney for O’Loughlin (61), N McCarthy for Gibson-Park (70), R Byrne for J Carbery (74)
John Lacey (IRFU)