2016-17: Ranked on three of NU's top times ... Ranked second at NU in 50 back and third in 100 back and 50 fly ... Won the 50 back against Iowa ... Finished fifth in the 50 back and 50 fly at TYR ... Won the 50 back in the tri-dual against UChicago and UIC.
2015-16: Member of 200 medley relay team that ranks fifth on NU's all-time depth chart with a time of 1:26.52 that came at the Big Ten Championships ... Qualified for and competed in the 100 back and 100 fly of the 2016 U.S. Olympic Trials, one of only three NU swimmers to qualify for two events.
2014-15: Versatile freshman who added depth across the board for Northwestern early in the year only to emerge as NU's top 100 back and butterfly swimmer at the Big Ten Championships … Had NU's fastest times of the year in the 100 backstroke and 100 butterfly while ranking fourth in the 200 back … Came out of nowhere at the B1G meet to make the consolation finals of the 100 back and 100 fly … His time of 47.40 in the 100 back prelims was an NCAA 'B' cut and made him the second-fastest swimmer in the event in NU history behind only 2012 100 back Olympic Gold medalist Matt Grevers (though Petersen was then DQ'd in the consolation final) … Placed 12th in the conference in the 100 fly with a career-best 'B' time of 47.36 in the consolation heat, a time that made him the fifth-fastest in NU annals in that event … Also made the bonus final of the 200 back at the B1G meet with a career-best and 'B' time of 1:45.61 before placing 24th overall … Scored points in four events while earning six second swims at Northwestern's home TYR Invitational (11/21-11/23) … Best finish was a championship final appearance and seventh-place result in the 100 back … Won the consolation final of the 50 back while finishing 10th in the 100 fly and 12th in the 200 back at the TYR … Also was 23rd in both the 50 free and 200 IM at the meet … Competed in four events at the AT&T U.S. Winter Nationals (12/3-12/6), swimming season-best times in the 50 free and 100 free … Scored dual meet points on eight occasions via top-five race finishes … Best dual finishes were third-place efforts in the 100 back against UIC/Oakland (10/25), the 200 back versus Milwaukee (1/16) and in the 100 fly against Eastern Michigan (10/16) and Iowa (1/24).
High School: Ranked as the 58th overall recruit in the nation and second overall in the state of Wisconsin by Collegeswimming.com ... Swam just two years of high school competition -- as a freshman and a junior -- and racked up four top-four state finishes including one state title ... As a freshman, finished third in the 100 back and fourth in the 100 fly at the Wisconsin state meet ... As a junior, set a state record to win the championship in the 100 back while also placing fourth in the 200 IM ... Earned all-state honors as a freshman and all-America accolades as a junior ... Holds Homestead High School team records in the 100 back and 100 fly in addition to five pool records across the Northshore Conference ... Swam club with Schroeder Swim Team beginning in 2011 ... Team won multiple state championships with state records while also earning two national titles during his time with the squad ... Honor roll member all four years of high school.
Personal: Born Nicholas Charles Petersen ... Son of Amy and Chuck Petersen ... Father swam at Northwestern as a member of the Class of 1983 ... Chose Northwestern over Indiana ... Major is political science.
PETERSEN'S PERSONAL BESTS
| Event | Personal Best |
| 100 backstroke | 46.93 |
| 200 backstroke | 1:45.61 |
| 100 butterfly | 47.25 |
| 50 freestyle | 21.45 |