OTTAWA — The Ottawa Redblacks didn't do themselves any favours in the CFL's East Division semifinal.

The Redblacks turned the ball over four times and saw their hopes of repeating as Grey Cup champions end with a 31-20 loss to the Saskatchewan Roughriders on Sunday afternoon.

It was Ottawa's first home playoff loss.

"It's very hard to win, especially turning the ball over," said Redblacks head coach Rick Campbell. "The two biggest indicators you can look at is turnovers and penalties, but the turnover thing is hard to overcome…they created some turnovers and we didn't.

"We never found a way to make key plays in the big moments of the game."

Ottawa quarterback Trevor Harris, who played his first playoff game, underperformed despite going 37 of 60 for 457 yards, two touchdowns and two interceptions.

"We're not going to sit here and make excuse. We just didn't get it done," said Harris, who is in the final year of his contract. "It hurts, but if it didn't hurt that would mean it didn't mean anything."

Harris threw an interception in the first half with Ottawa on Saskatchewan's ten-yard line and an incomplete pass forced the Redblacks to settle for a field goal early in the second half while deep in Roughriders territory.

Saskatchewan scored a 75-yard touchdown to take a 28-11 lead on the next play.

"I don't want to say we lost the game, but we shot ourselves in the foot early on that we gave them the game and we gave them the momentum and you can't do that," said Redblacks fullback Patrick Lavoie. "I think this is a team that we're capable of beating, but we shot ourselves in the foot and we didn't finish our drives and I think defensively we were a little surprised by Marcus Thigpen's speed."

Missed assignments on defence allowed the Riders to get wide open on offence and gain favourable field position throughout the game.

Saskatchewan was 12-for-22 on second down conversions, compared to just 10-for-27 for Ottawa.

"They just had more big plays than we had today," said Redblacks linebacker Taylor Reed. "Defensively we gave up a big play to Thigpen and plays like that and in the playoffs when you're trying to win against a good opponent you can't have those mistakes."

The sting of the loss was that much deeper for the Redblacks knowing the Grey Cup will be played in Ottawa in two weeks.

"To come up short in the semifinal, it's heartbreaking," said Ottawa centre Jon Gott. "I feel bad for my teammates, I feel bad for the fans. I thought we were going to go further than this."