To me Rielly has always been a winner, because his been way better in the playoffs than in the regular season. It's no surprise to me. Off course there is certain limit in his abilities, that he probably never is really top10 defender in the NHL, but in the playoffs his close and almost always close to his best. That makes him winner although team around him doesn't always deliver, but I can't blame Rielly when I complain about our playoffs record.
Last few years I think two core players that get clean sheet from me are Rielly and Nylander. Nylander has been money and effective basically always. He has some tendencies I don't like and he can be frustrating, but still his been usually excellent. Rielly has been the same, usually elevating his game and being effective.
Marner, Tavares and Matthews have been disappointing at times. They could have done more with their talent and have the ability to carry us trough tough games. Matthews and Marner are fairly young so they can still learn, but in my eyes Tavares should have been what ROR is at the moment.