John Callahan transferred to Northwestern with sophomore eligibility after competing at Santa Clara University in 2010-11
2013-14: Competed in three events during the season including two as a member of the team lineup ... In the fall, defended his 2012 Windon Memorial Classic championship as an individual at the 2013 installment ... Fired an even-par 72 in the second round of that event (Sept. 22) en route to a 57th-place result ... Qualified to join the team lineup in the spring at Ohio State's Kepler Intercollegiate where he finished 66th ... Again qualified for the team lineup and competed in his final collegiate tournament at the NCAA San Antonio Regional (May 15-17) ... Served the Northwestern community as the vice president on the Student-Athlete Advisory Committee (SAAC) ... Male winner of the Northwestern "Willie Award" given by the NU P.R.I.D.E. organization for student development.
2012-13: Competed in five tournaments, three as an individual and two in the team lineup ... Playing as an individual, won medalist honors at Northwestern's own Windon Memorial Classic in October with a 1-under 212 for his first-collegiate win ... Opened that tourney with a career-best 2-under 69 before also shooting a final-round 69, draining a 25-foot birdie putt on his 54th hole to win by one ... Named Big Ten Golfer of the Week after the win ... Appeared twice in the team lineup after that victory with his best round coming in an even-par 71 to open the Gifford Collegiate at CordeValle (11/5) ... Owned NU's third-best scoring average (74.22) after the fall season ... After opening with an 81, recovered to fire back-to-back 1-over 73s at Northwestern's Spring Invitational (4/15-4/16).
2011-12: Competed in Northwestern's final two fall tournaments, finishing 52nd as an individual at the Windon Memorial Classic (Oct. 16-17) and 48th as a member of the team lineup at the Gifford Collegiate at CordeValle (Oct. 31-Nov. 2) ... Also competed in the team lineup at the Barona Collegiate Cup (March 22-23).
2010-11 (at Santa Clara): Competed in three events for the Broncos including the WCC Championships ... Finished 36th in that event after carding a final-round even-par 72 ... Tied for 48th at the Anteater Invitational ... Tied for 63rd at the SCU Cabo Collegiate, recovering from a pair of rounds in the 80s to fire a final-round 74.
High School: Qualified for the Illinois state tournament as a sophomore, junior and senior, earning all-state honors as a sophomore after a fifth-place finish ... Led Benet Academy to an eighth-place team finish at the Illinois Class 3A tourney as a junior ... Two-time Naperville Area Player of the Year ... Three-time East Suburban Catholic All-Conference choice ... Competed in the Illinois Amateur in 2008 and 2009 ... Earned top-10 finishes in the AJGA Columbus event (fifth) and the AJGA Golf Pride tournament (eighth) ... National Honor Society member ... National Merit Scholar ... Honor Roll.
Personal: Born John Ryan Callahan ... Son of Peggy and Kevin Callahan ... Went to high school with Northwestern men's basketball student-athlete Dave Sobolewski ... Chose Northwestern over Notre Dame during the transfer process ... Majoring in economics.
| Season | Rounds | Strokes | Average | Low |
| 2010-11 (at Santa Clara) | 9 | 706 | 78.44 | 72 |
| 2011-12 | 9 | 688 | 76.44 | 72 |
| 2012-13 | 15 | 1,132 | 75.47 | 69 |
| 2013-14 | 9 | 703 | 78.11 | 72 |
| Career | 42 | 3,229 | 76.89 | 69 |