Leinonen’s first North American season has looked more like an adjustment year than a clean breakout. Buffalo gave him an early test in the September Prospects Challenge, where the smaller rink and added net-front traffic were immediate parts of the learning curve after his time in Finland and Sweden. He still settled enough to earn his first AHL win in late October, stopping 25 of 28 shots in just his second game with Rochester.

The bigger issue after that was rhythm. Leinonen’s Rochester sample stopped at seven appearances, and his AHL line sat at 3-3-0 with a 3.11 goals-against average and .868 save percentage. A lower-body injury in December interrupted that runway, and by February Buffalo had reassigned him to Jacksonville. Rochester later made clear the ECHL move was also about getting him more playing time.

That late-season Jacksonville stretch has at least given him live reps again. He has gone 3-1 in five ECHL games with a 2.75 goals-against average, and the late-March results were better than the stop-start season as a whole: 19 saves on 20 shots in a March 23 win over Greenville, then 26 saves on 28 shots the next weekend in his second start in under 24 hours. The read here is still long-view. This year did not make him an NHL option, but it did finally move him from European projection into North American pro minutes, which is the development step Buffalo needed.

Leinonen is due to move across the pond this fall, slated to join the Rochester Americans of the AHL. After playing the majority of this career at various Finnish levels, he played for Mora IK of the Hockey Allsvenskan in 2024-2025. The move suited him well, given that despite a 13-10-0 record, Leinonen sported a 2.31 GAA and .910 save percentage, which were his best rate stats at any level aside from a 2021 stint in the U20 Sarja where he posted a 2.28/.916 mark.

Leinonen’s numbers sat 6th in Save Percentage, and 5th in GAA in the Allsvenskan, and given that it not only is just one season, but nearly the only season he performed so well, it will be hard to project what we should expect in the AHL. At 6-5 and 235 pounds, he is a big bodied netminder with good positioning, and will turn only 22 in January. He has a lot of runway ahead of him, but also isn’t primed for an NHL job just yet. Given the uncertainty with goalie development, he’d be worth stashing just on proximity alone, but he isn’t a lock to play meaningful games for your fantasy squad for the next few seasons.