The 103 rd pick overall in the 1986 NHL Entry Draft, John Purves attended the Washington Capitals training camp in the fall of 1988. While he didn't make the team he did take back information on areas of his game to improve. John must have taken the information to heart as he recorded 102 points in just 47 games. He didn't make the team in the 1989 training camp and was left behind when the Capitals left for a pre-season European tour. At the end of camp he was assigned to his first professional team in Baltimore.
Even though he recorded 64 points in his AHL rookie campaign Purves still wound up with the Skipjacks at the beginning of the 1990-91 season. Shortly after the season began the Capitals lost Alan May and Dino Ciccarelli to injuries which forced the forward depleted Washington team to call up John Purves. He made his debut in Calgary on September 27, 1990.His coach, Terry Murray, described his play as being tentative and flatfooted at times. John agreed by saying, "It' s definitely faster. It' s a given that it would be quicker skating-wise, but it is also two steps quicker in terms of reaction time. You can' t stand still. You've got to be moving all the time and anticipating the play." Purves almost had his first point in Vancouver but had a Canuck touched the puck before the Capitals recovered for the goal.
His first point came on November 3 in Uniondale while facing the Islanders. A goal mouth scramble resulted in the puck deflecting off the right wing and past Glenn Healy for Purves' first and only NHL goal. John Purves returned to the minors in mid-November when the Capitals sick bay emptied. He was called up in January 1992 for an exhibition game between the Capitals and Team USA before the 1992 Winter Olympics. After the season he departed for a team in Germany and a greater paycheck than the AHL offered. Purves returned in 1993 to play in the International Hockey League and was there until it folded in 2001. John " Never Nervous" Purves moved to the American Hockey League Utah Grizzlies for the 2001-02 season.