Combining strong passing skills with excellent mobility helped Phipps establish a new school single-season record for total offense and earn the Boilermakers a share of the Big Ten Conference title.

[2] The following year, Phipps suffered an ankle injury that kept him out of two games, and was overshadowed by teammate Leroy Keyes, a running back who spent all season in contention for the Heisman Trophy.

In the team's third game of the 1970 NFL season, Phipps came off the bench to lead a 15–7 comeback victory over the Pittsburgh Steelers.

However, his lone start of the year would be a 14–10 loss to the Cincinnati Bengals on November 15, 1970, as the rookie finished with 529 passing yards on the season.

In 1972, Phipps again began the season on the sidelines, but became the team's starting quarterback after a disappointing 26–10 opening game loss to the Green Bay Packers on September 17.

That finish came on May 3, 1977, when Phipps was traded to the Bears for a first-round draft pick in 1978, which turned out to be Hall of Fame tight end Ozzie Newsome.

During that year, he threw for 1,535 yards and nine touchdowns, as he battled teammates Bob Avellini and Vince Evans for playing time.

Phipps threw for a pair of touchdowns in each of the next two seasons, but his limited role and the arrival of both quarterback Jim McMahon in the 1982 NFL draft and new coach Mike Ditka resulted in his release.