Hawk Item — 2013 NCAA qualifier… finished his career as the school-record holder as member of the 800-free relay (6:26.79)… also had the fifth-fastest time in 200 free (1:36.04).
2015-16 — Posted an NCAA “B” qualifying time in 200 free (1:37.58) to lead the team… honorable-mention CSCAA Scholar All-American… swam collegiate-bests in 50 free (20.37) and 100 back (49.60)… had season-best time of 44.77 (100 free)… member of team-leading 400-free relay (2:56.37) and 800-free relay (6:27.83)… scored in two events at 2016 Big Ten Championships… placed sixth in 800-free relay (6:27.83) and was 24th in 200 free (1:38.11)… won the 200 free in dual against Western Illinois (2/5)… also was a member of three winning relays… Academic All-Big Ten and Big Ten Distinguished Scholar selection… named to UI’s Dean’s List for fall semester.
2014-15 — Was second on the team in the 100 free (44.52) and third in the 200 free (1:37.38) with an NCAA “B” qualifying time… member of team-leading 400 free (2:55.44) and 800-free (6:29.57) relays and third-fastest 200 free relay team (1:22.78)… top times in the 400 and 800 free relays rank seventh all-time… posted 24 top-5 finishes… named Academic All-Big Ten… letterwinner.
2013-14 — Led team in the 100-free (44.41) and 200-free (1:36.66)…was a member of the team-leading 200 free relay (1:20.24), 400 free relay (2:57.20), 800 free relay (6:31.59), and 400 medley relay (3:10.58)… recorded an NCAA “B” qualifying time in the 200-free while recording a NCAA provisional time as part of the 400 medley relay… swam a collegiate best in the 50-free (20.41) at the Hawkeye Invitational and a collegeiate best in the 100-free (44.41) at Big Ten Championships… recorded 10 top-five individual finishes, including two victories, and 12 top-3 finishes in relays… recipient of the Wally Ris Memorial Award… Academic All-Big Ten… letterwinner.
2012-13 — Swam on the 800-free relay at the NCAA Championships that finished 27th overall (6:29.96)… won the “B” final and finished ninth in 200 free (1:36.04) at the Big Ten Championships… led team in the 200 free with an NCAA “B” qualifying time of 1:36.04 and posted the second-fastest 50 free (20.42) time… swam collegiate best times in the 50 (20.42), 100 (44.47), and 200 (1:36.04) free at the Big Ten Championships and 100 fly (51.06) in dual at Indiana/vs. Ohio State…. swam on team-leading 200 (1:19.82), 400 (2:56.07), and 800 (6:26.79) free relays… the 800 free relay set a school record at the Big Tens… posted nine top-five finishes, including one first-place finish… letterwinner.
High School — Won the 100 fly with a time of 58.45 at the 2008 Swedish Youth Championship… finished third in the 200 free at the Swedish Nationals with a time of 1:48.93… Swedish Olympic Trial qualifier… best times are 20.30 (50 free), 43.82 (100 free, 1:36.94 (200 free) and 48.90 (100 fly)… swims for the Stockholm Polisens SIM IF… coached by Sven Rowe Malmberg.
Personal — Born July 23, 1992… son of Mikael and Sofia Ernstsson… has two siblings, Emelie and Hampus… majoring in finance.
Ernstsson’s Collegiate Bests
| Event | Time | Meet | Date |
| 50 Free | 20.37 | at Big Ten Championships | 2/25/16 |
| 100 Free | 44.41 | at Big Ten Championships | 3/1/14 |
| 200 Free | 1:36.04 | at Big Ten Championships | 3/1/13 |
| 100 Back | 49.60 | Hawkeye Invitational | 12/5/15 |
| 100 Fly | 51.06 | at Indiana/vs. Ohio State | 1/19/13 |
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