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Sebastian Cossa
Goaltender · UTA · NHL

Sebastian Cossa

Age
23
Height
6'6"
Weight
221 lb
Catches
L
Drafted
2021, round 1, 15th overall
Born
CAN
2026-27
NHL · Utah Mammoth
Games
2
Save pct
.852
GAA
3.16
Prospect score · 2026-27
High end

36th of 1,160 prospects in the NHLnew

2nd in the UTA system · 1st among its goalies

+1.3WAR a season if he sticks
Outlook
NHL odds81%Becomes a full-time NHL player — 100 games by 27
Impact odds35%Better than the typical NHL regular among goalies
Arrival2028-29The season his comps who made it typically became regulars
WAR a season if he sticks+0.5+1.3+3.5Low, middle and high outcomes among his comparables who became regulars

Of the 10 players most like him at the same point in their development, 5 became full-time NHL players.

Development

His save percentage, adjusted for league, against every goalie his age that season. Zero is the average player his age; the band is where his comparables were at each age.

-2-10+1+216171819202122Age2019-20, age 16, 33 GP: +0.71 vs. his age group2020-21, age 17, 19 GP: +1.23 vs. his age group2021-22, age 18, 46 GP: +0.57 vs. his age group2022-23, age 19, 46 GP: +0.66 vs. his age group2023-24, age 20, 40 GP: +0.62 vs. his age group2024-25, age 21, 41 GP: +0.52 vs. his age group2025-26, age 22, 39 GP: +1.32 vs. his age group
HimMiddle half of his comps at that ageAverage player his age
Comparables

Past prospects at the same position and the same stage after their draft, matched on draft slot, age, size and league-adjusted production. What they became is already known. The outcome is judged at 27: 100 NHL games by then makes a regular.

#PlayerMatchNHL GP by 27Career NHL GPOutcomeWAR a season
1Magnus Hellberg2011 · #38 · at 2330%426Did not stick—
2Malcolm Subban2012 · #24 · at 2329%8687Did not stick—
3Tom McCollum2008 · #30 · at 2329%33Did not stick—
4Jack Campbell2010 · #11 · at 2327%64176Regular after 27—
5Jacob Markstrom2008 · #31 · at 2227%169583Regular+3.47
6Ilya Samsonov2015 · #22 · at 2125%200200Regular+0.91
7Jake Allen2008 · #34 · at 2224%219501Regular+2.51
8Anthony Stolarz2012 · #45 · at 2224%62171Regular after 27—
9Anders Nilsson2009 · #62 · at 2224%105161Regular+1.28
10Thatcher Demko2014 · #36 · at 2123%219262Regular+2.28
Season by season
SeasonGPRecordSv%GAASO
2026-27NHL · Utah Mammoth21-1-0.8523.160
2025-26AHL · Grand Rapids Griffins3926-8-4.9152.335
2024-25NHL · Detroit Red Wings11-0-0.8572.670
2024-25AHL · Grand Rapids Griffins4121-15-5.9112.451
2023-24AHL · Grand Rapids Griffins4022-9-8.9132.412
2022-23ECHL · Toledo Walleye4626-16-1.9132.564
2022-23AHL · Grand Rapids Griffins31-1-0.7835.570
2021-22WJC-20 · Canada U2011-0-0.9172.000
2021-22WHL · Edmonton Oil Kings4633-9-3.9132.286
2020-21WHL · Edmonton Oil Kings1917-1-1.9411.574
2019-20WHL · Edmonton Oil Kings3321-6-3.9212.234
2018-19WHC-17 · Canada White U1721-1-0.8953.030
2018-19AMHL · Fort Saskatchewan Rang. U18 AAA136-5-2.9193.011
2018-19AEHL U18 · Fort Saskatchewan Ranger U18 AAA136-5-2.9193.011
2017-18AEHL U18 · Fort Saskatchewan Ranger U18 AAA196-10-3.9153.370
2016-17AEHL U15 · Fort Saskatchewan Ranger U15 AAA1915-4-0.9341.805
2015-16NAHL U15 · Fort McMurray Oil Barons U15 AA140-0-0.9262.600

The prospect score is a percentile of his expected outcome among every prospect in the league: the chance he becomes a regular, times how good his comparables who did became against others at their position. A player who never sticks counts as zero, which is why a long shot with a high ceiling can rank below a safe bet. Goalie projections carry the widest error on the site — goaltending develops late, and there are few goalies to learn from. All Sabres prospects · How the rankings work