MONTREAL (Ticker) -- The battle for supremecy in the CFL turned into a mismatch.

In a matchup of the league's top two teams, the Montreal Alouettes rode the arm of Anthony Calvillo and handed the Calgary Stampeders their first loss of the season, 48-13.

Calvillo ripped apart the Stampeders' secondary, completing 19-of-30 passes for 366 yards with three first-half touchdowns.

In the first quarter, Calvillo found Kevin Alexander with a 15-yard TD pass. He added a 17-yard scoring strike to Alexander in the second period and a 73-yard bomb to Ben Cahoon with 57 seconds left before intermission to help Montreal (6-2) open a commanding 31-13 lead.

Tyree Davis had three receptions for 107 yards and Cahoon had four catches for 102 yards.

Calgary (6-1) scored its lone touchdown early in the second quarter when Marc Boerigter recovered a blocked punt in the end zone.

Stampeders quarterback Dave Dickenson went 14-of-19 for 139 yards.