Ticats quarterback Matthew Shiltz suited up for the first half and completed 10 of his 16 pass attempts for 162 yards and two touchdowns and added one run for 51 yards, which set up an 18-yard field by Jonathan Garibay just over three minutes into the contest.
QB Cody Fajardo played well in his first game with Montreal, going 7-for-14 for 77 passing yards and tossed a 3-yard touchdown to receiver Kaion Julien-Grant to give the Alouettes a 7-3 lead in the opening quarter.
After Hamilton’s Blake Hayes booted a punt single, Shiltz connected with receiver Richie Sindani on a 10-yard TD and then threw a 21-yard touchdown to Terry Godwin as the Cats grabbed an 18-13 lead late in the first half.
Two field goals by David Cote from 45 and 38 yards, and a three-yard touchdown run by running back Walter Fletcher put the Alouettes back on top, 19-18 at the half.
Ticats punter Bailey Flint earned a single point with under a minute to play in the third quarter, the only scoring in that period.
Two field goals pushed the Alouettes to a 25-19 lead early in the fourth quarter before Ticats kicker Ethan Ratke split the uprights from 43-yards out to make it a three-point game again with just under five minutes remaining.
Backup QB Taylor Powell played the second half for Hamilton and went 9-for-15 for 122 yards and one interception while running back Tayon Fleet-Davis rushed a game-high seven times for 25 yards.
The Tiger-Cats will begin the regular season on June 9 in Winnipeg.