After spending one season as part of Leinster's senior team, during which time he failed to make any appearances for the first team, Keatley joined rival Irish province Connacht ahead of the 2008–09 season. Keatley made his first appearance for the side on 5 September 2008, starting in a 2008–09 Celtic League match against the Ospreys. Keatley played in 17 of Connacht's 18 league games for the season, starting in all of the matches he played. Keatley also made his European debut that season on 10 October 2008, starting in the team's 2008–09 European Challenge Cup game with French side Dax. Of Connacht's six games in the group stages of the competition, Keatley started five, missing a match against London Irish. Keatley also started in Connacht's quarter-final defeat to eventual champions Northampton Saints. He scored a total of 185 points for the province during the course of his first season.