MONTREAL -- Montreal Alouettes coach Tom Higgins said this week he was waiting for his offence to explode, and they picked a playoff game to do it.

With third string running back Brandon Rutley leading the way with 95 yards on 15 carries, the Alouettes piled up 215 rushing yards in a 50-17 trouncing of the B.C. Lions in the CFL East Division semifinal on Sunday afternoon.

"It's a great feeling to be doing this and be in this position," said Rutley, who stepped into the lineup when Tyrell Sutton hurt an ankle in the final regular season game, a 29-15 loss at Hamilton. "We have so much talent and, when it comes together like this, it's magic out there."

The victory bought Montreal a return ticket to Hamilton to face the Tiger-Cats in the East final next Sunday.

They hope to stay on the roll that started in mid-season, when they bounced back from a 1-7 start to win nine of their next 11 games.

Jonathan Crompton completed 14 of 21 passes for only 155 yards, but they included touchdown tosses to S.J. Green and Duron Carter. The Alouettes tied a team record for rushing TDs in a playoff game with four, as backup quarterback Tanner Marsh ran in twice and Rutley and Chris Rainey each scored one.

Defensive back Jerald Brown also scored on a team-record 103-yard fumble return.

B.C. ended its season with only two wins in it's last eight games. Including one-sided losses to Edmonton and Calgary to end the regular season, the Lions were outscored 120-36 in their final three games.

The Lions finished fourth in the West but crossed over because they had a better record than the East's third-place team, the Toronto Argonauts. Montreal is 4-0 all-time against crossover opponents, with three of those wins against the Lions.

B.C. starting quarterback Kevin Glenn went 6 for 18 for only 64 yards with two interceptions before Travis Partridge took over in the third quarter. Star QB Travis Lulay, who missed 20 of the last 21 games, dressed but was not deemed fit enough to get into the game.

"There's no way to explain it," said B.C. coach Mike Benevides, whose team trailed 50-3 before Partridge threw late TD passes to Shawn Gore and Ernest Jackson, mostly against Montreal's second string defenders.

"The third quarter was disastrous. At halftime, it was a 12-point game. They executed at a high level. They made plays and we didn't make any."

Montreal led 15-3 at the half, but broke open the game with 21 points in the third quarter on three rushing TDs.

"We were getting good push up front," said Montreal tackle Josh Bourke. "We stuck with the run game.

"When playoff football occurs, it's about running the ball and playing good defence. We made some nice touchdown passes in there too, but we set the tone by running the ball."

Rutley had quite a season. He was invited to training camp after a tryout, but was let go. When tailback Brandon Whitaker was injured late in the season, he was called back and put on the practice roster. Then Sutton went down and he suddenly became the starter.

"It's an amazing journey and I want it to continue," said Rutley.

Now the Alouettes need to carry the confidence gained against B.C. into Hamilton, where they lost with turnovers and weak play in the regular season finale.

"That's the regular season, they won that one," said linebacker Bear Woods. "We're going to win this one.

Asked if that meant he was guaranteeing victory," Woods said: "I'm guaranteeing it and I hope they're guaranteeing they'll beat us. That's the mentality that both teams have. It'll make for a great football game for all the fans in the CFL."

There were plenty of empty seats at Percival Molson Stadium as only 15,107 turned out to the 23,500-seat venue on a chilly day with a few snowflakes. There wasn't a lot to see until late in a slow first half marked by dropped passes on both sides, but then Montreal took apart the B.C. defence the rest of the way.

The first quarter saw only Sean Whyte's punt single go up on the board.

The Lions thought they'd thwarted a drive when Adam Bighill intercepted near the goal-line, but an illegal contact penalty on Cord Parks instead gave Montreal the ball on the B.C. 10. On the next play, Crompton found Green behind Parks in a corner of the end zone at 9:20 of the second.

Glenn answered with an eight-play drive capped by Paul McCallum's 30-yard field goal.

A roughing call against Ryan Phillips helped keep alive Montreal's return drive and Crompton hit Carter over the middle for a TD at 13:51 for a 15-3 halftime lead.

Montreal opened the second half with a nine-play 79-yard drive on which Rutley carried four times in a row to the B.C. 2. Marsh ran it in at 5:25.

Woods picked off a Glenn pass and, set up by a 29-yard toss to Green, Rutley ran in from the four at 10:41 to all but put the victory in the bank.

Things got strange when Partridge took over at QB for the Lions' next possession. He threw a short pass to Marc Ianuzzi, who attempted to punt the ball only to see it dribble forward, giving Montreal the ball on the 3. Marsh ran it in two plays later at 13:01

As if things couldn't get worse for B.C., Tim Brown ran a kickoff back to the Montreal 12, only to see Stefan Logan fumble and Brown run it back 103 yards for a TD at 4:01 of the fourth quarter.

Finally, with 2:14 left, Partridge found Gore for an eight-yard TD pass and Logan scored the two-point convert. Brown returned a punt to the Montreal eight and Partridge hit Jackson for the TD, but this time, the two-point attempt failed.

It was the most points Montreal has scored this season. Their next best was a 38-31 win at home over Hamilton on Sept. 7.

"It was a team win,"said Woods. "Our offence was able to score points.

"It's been rare that we've had that type of support from our offence, to where our defence got some rest and was able to play at that high level the whole game."

Alouettes defensive end John Bowman left with a rib ailment in the third quarter and did not return. Higgins said Bowman could have come back but they decided to keep him out as a precaution.

As for the weak attendance, Alouettes president Mark Weightman said it was tough selling an outdoor game in November when the team only found out it would be in the semifinal last week.

"We've had a great sequence to end the season, but we've had a couple of years now where we haven't had as much success," he said. "I don't think a good second half is necessarily going to re-convince 100 per cent of your fans, you need to show you can win consistently over a longer period of time.

"There were probably still some skeptical fans who weren't sure about this game and thinking what would happen. Hopefully, 50-17 will convince them."

Notes -- The last time Montreal scored 50 points in game was the opening week of 2010, a 54-51 loss in overtime to Saskatchewan. . . The loss ends the run of three straight years in which a team playing at home won the Grey Cup. The championship game is slated for Nov. 30 in Vancouver.. . B.C.'s Logan had 13 carries for 94 yards, but the Lions had only 102 passing yards.