Stampeders 27, Redblacks 3: Bo Levi Mitchell threw for 166 yards and a touchdown before suffering a knee injury as visiting Calgary shut down Ottawa to remain the league's only unbeaten team.

Mitchell completed 16-of-21 passes before a late hit in the second quarter knocked him out of the game and Nick Arbuckle (8-of-14) threw for 84 yards and a touchdown in relief as the Stampeders improved to 4-0 for the first time since 2014. Don Jackson rushed for 102 yards on 15 carries while Juwan Brescacin and Lemar Durant each caught a touchdown pass for Calgary, which scored 12 points off five turnovers.

Trevor Harris was limited to 93 yards on 14-of-22 passing for the Redblacks, who fell to 2-2 - with both losses coming against Calgary. William Powell was held to 17 rushing yards after racking up 138 in the Week 4 victory over Montreal while Brad Sinopoli caught four passes for 37 yards for Ottawa, which mustered only 150 yards of total offence.

Romar Morris rushed for a 1-yard touchdown and Mitchell hit DaVaris Daniels for the two-point conversion to put Calgary in front 8-0 after one quarter. Mitchell fired a 10-yard scoring strike to Brescacin and Rene Paredes tacked on a pair of field goals (17, 25 yards) as the Stampeders outgained the Redblacks 239-27 en route to a 20-0 halftime lead.

Ottawa marched down the field on the opening possession of the second half but had to settle for an 11-yard field goal from Lewis Ward, which closed the gap to 20-3. Durant caught a 12-yard touchdown pass from Arbuckle with 10:04 remaining in the fourth quarter to put the Stampeders in total control as they cruised to their first win in the nation's capital since Aug. 24, 2014.

GAME NOTEBOOK: Calgary WR Eric Rogers, who caught three touchdown passes in his previous two games, missed the contest due to a sore knee. … Ottawa WR Greg Ellingson made three catches for 26 yards to extend his streak of games with at least one reception to 31 in a row. … The Stampeders improved to 17-0 when coming off a bye since 2005. … Stampeders WR Kamar Jorden hauled in six passes for 79 yards.