TORONTO – Petr Mrazek waited just 16 days after his first groin injury as a Toronto Maple Leaf to slide back in the crease. He immediately reaggravated the injury. In hindsight, the return was rushed. Exercising caution, Mrazek and the team delayed 42 days this time before giving his groin another test Saturday versus the Chicago Blackhawks. Yes, following a month and a half of Jack Campbell holding down the fort (and feel-good story Joseph Woll popping up for a winning record), Mrazek will once again attempt to jumpstart his Leafs career. Take 3. “Feeling good,” an upbeat Mrazek said. “Especially when you’re on a new team, you want to compete, you want to win games. That’s how it is. Especially with goaltenders, you have to be careful with groins. You have to make sure it’s healed well.” To that end, the Leafs had Mrazek play a game with the AHL Marlies on Sunday (he gave up four goals in a loss to Laval), and the veteran appreciated the tune-up exercise. In his five periods...