After the 1965-1966 season, Mariucci was dismissed of his coaching position by A.D. Marsh Ryman.Glen Sonmor, a former Minneapolis Millers and professional hockey player and experienced coach, who at one time had been Mariucci’s freshman coach, became the Gophers seventh mentor.
In five seasons plus part of another, Sonmor posted a 79-82-6 record. After he left early in the season of 1971-1972 to join the newly formed Minnesota Fighting Saints of the World Hockey Association (WHA), he was replaced by interim coach Ken Yackel.
With a season record 21-12, and a 18-8 finish in the WCHA, the Gophers captured the 1969-19760 season title edging out Denver and Michigan Tech. Goalie Murray McLachlan and the pint-sized Mike Antonovich from Greenway of Coleraine led the Maroon and Gold to the league championship. In the finals of the WCHA playoffs, Michigan Tech edged the Gophers 6-5 to dash any hopes that they had of going to the NCAA tournament. In 1971 the upstart Gophers, saddled with a losing regular season of 11-16-2, advanced to the NCAA finals at Syracuse before losing to Boston University 4-2. In the semi-final game Minnesota edged Harvard 6-5. Frank Sanders, Mike Antonovich, Dennis Erickson, John Matschke, Wally Olds, Craig Sarner, Doug Peltier and Dean Blais were among the players who took a leading role in the surprising finish of the 1971 team. McIntosh and Blais were selected to the All-Tournament NCAA team.
From the Sonmor era, Wally Olds (1970), Gary Gambucci (1968), and Murray McLachlan (1970), were chosen to the All-American team. In 1968 Bill Klatt led the WCHA in scoring with 23 goals and 20 assists in 31 games.
Players from this period who became members of the U.S. Nationals or the U.S. Olympics were Peter Fichuk, Bruce McIntosh, Wally Olds, Frank Sanders, Craig Sarner, Dean Blais, Mike Polich, Mike Antonovich, Gary Gambucci and James Branch. Players from this era who turned professional include: Mike Antonovich, Bill Butters, Dean Blais, Brad Buetow, Bill Klatt, Bruce McIntosh, Craig Sarner, Frank Sanders, Gary Gambucci and Pat Westrum.
Teams met during this time, not played previously, were St. Lawrence, Ohio State and Colgate. Three new teams joined the WCHA during this period- Minnesota Duluth in 1966-1967, Wisconsin in 1969-1970 and Notre Dame in 1972-1973.