CBC’s loss was TSN’s gain in the first round of the Stanley Cup playoffs, as the pubcaster saw a slight drop in audiences over last year, while TSN enjoyed an increase of 42% for its coverage that included a Canadian team for the first time.

CBC averaged 948,000 viewers across round one, down 17%, which featured only two Canadian teams (Montreal and Vancouver), while TSN was able to showcase the Calgary Flames, courtesy of last year’s deal with the National Hockey League.

The Vancouver/St. Louis series was the most-watched on the Ceeb with an average 1.5 million viewers — that saw the Canucks move on to the second round — followed by Montreal/Boston with 1.1 million, as the Canadiens were ousted in four games. Meanwhile, CBC’s U.S. series averaged 624,000 viewers. (All numbers 2+.)

TSN’s first-round coverage scored an average 567,000 viewers versus 399,000 in 2008, with the Flames fetching 879,000 viewers per game — predictably the cabler’s most-watched series. (The Flames were eliminated in six games.)

Over on RDS, the Canadiens’ poor showing meant fewer viewers on average than last year on the French caster, as numbers dropped from 716,000 to an average 351,000 viewers for the first round. RDS’ highest-rated game of the post-season was the April 20 bout between Montreal and Boston, which generated 1.2 million viewers.

CBC should see loftier numbers for the second round, with coverage of the western conference semifinal featuring Vancouver and Chicago, and the high-profile eastern conference matchup between Sidney Crosby’s Pittsburgh Penguins and the Washington Capitals, led by top-scorer Alex Ovechkin.

TSN has the Boston/Carolina series in the east, and the western semifinal featuring Detroit and Anaheim.