VANCOUVER, British Columbia (AP) -- The B.C. Lions continued their domination of the Calgary Stampeders Saturday night, rallying for 17 second-half points and a 21-20 victory that gave them sole possession of first place in the CFL West.

It was B.C.'s third win of the season over the defending Grey Cup champions and fifth consecutive defeat of Calgary dating back to last year. Lions coach Greg Mohns improved to 5-0 against the Stampeders coach Wally Buono.

Adding insult to humiliation, Buono was ejected with just over 12 minutes left in the fourth quarter. Lions quarterback Damon Allen had just hit Don Blair on a key third-and-two gamble and Buono was called for abuse of an official after arguing the placement of the ball.

It was the first time Buono had been ejected in 10 years as a head coach.

After trailing 17-5 at the half, the Lions thrilled a season-high crowd of 28,431 by clawing their way back into the game. Allen cut the deficit with a one-yard touchdown plunge late in the third quarter, then B.C. took the lead 21-20 early in the fourth on a 7-yard Robert Drummond run.

Lions kicker Lui Passaglia hit on field goals of 25 and 47 yards plus added a 43-yard single.

Calgary quarterback Dave Dickenson hit Travis Moore with a 14-yard touchdown pass and Kelvin Anderson scored on a 7-yard run.

Mark McLoughlin added field goals of 31 and 19 yards.

The win gave the Lions a 9-3 record, best in the West. Calgary is second at 8-4.

Dickenson had a shaky start, including an interception that set up a Lions field goal. He finally settled down and marched the Stamps on a 10-play, 80-yard drive late in the first quarter that ended in the touchdown pass to Moore.

The Lions threatened before the quarter ended when Calgary's Kevin Johnson was called for pass interference on Robert Drummond, giving B.C. a 47-yard gain and first down on the Stampeder 33. But on the next play Allen fumbled and Calgary recovered.

Calgary took a 17-3 lead in the second quarter after Alfred Jackson coughed up a fumble that the Stampeders recovered on the Lions' 32. Three plays later Anderson scored.

Penalties proved costly to the Lions. A holding call wiped out a long Drummond pass reception in the second quarter, then Jimmy Cunningham's 75-yard punt return for a touchdown was also called back for an illegal block.

In the third quarter, with the Stampeders leading 20-14, Anderson looked like he was going to score on a 31-yard run, only to have the ball stripped from his hands on the goal line and recovered by the Lions Reggie Carthon.