The biggest competition the ever faced came in the 1970s from the World Hockey Association (WHA). It was founded in 1971 by Dennis Murphy and Gary Davidson, who had also been heavily involved in the NBA's challenger, the ABA. The WHA tried to challenge the NHL in a number of underserved hockey markets in North America. At the time, the NHL had expanded from six to twelve teams for the first time with the 1967 expansion. However, there were still numerous markets available that had an interest in hockey or successful minor league teams. Thus, the WHA entered and pushed the NHL both in terms of markets and also in player loyalty. Most famously, the WHA signed Bobby Hull to a 10-year, $2.75m deal, a record at the time. However, money would always be trouble in the WHA, with teams folding and moving cities all the time. About half a dozen teams in the league were solid, but rest of the league was almost constantly in flux. By 1979, the league was down to only seven teams and at long last agreed to a merger with the NHL that saw four teams absorbed (Edmonton, Hartford, Quebec, Winnipeg).