Chris Bassitt will finish out the rest of the regular season on the injured list.
The Toronto Blue Jays placed the right-handed starter on the 15-day IL with lower back inflammation, the team announced Saturday.
In a corresponding move, lefty Mason Fluharty has been recalled from triple-A Buffalo and will be active against the Kansas City Royals on Saturday night.
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The 36-year-old Bassitt owns a 3.96 ERA and 166 strikeouts across 31 starts this season, earning an 11-9 record. His last start came on Sept. 18 against the Tampa Bay Rays, where he allowed eight hits and three earned runs in 4.1 innings of work.
Manager John Schneider said Bassitt’s back has been acting up for the past three to four starts. The Blue Jays are “waiting on some further testing and stuff to see the plan going forward,” Schneider said. “Hopefully it’s fairly quick.”
The Blue Jays will keep the rest of their current rotation on regular rest and start Kevin Gausman, Max Scherzer and Shane Bieber against the Red Sox after their off day on Monday. Toronto’s starters for their final series of the season against the Rays are undecided.
Bassitt’s 15-day stint on the IL will finish on Oct. 3, which would make him eligible to return before the start of the ALDS.
Fluharty, 24, has been in triple-A since Aug. 24 after struggling to find the zone in his last three appearances with the big club.
In 11 appearances with the Bisons since his reassignment, Fluharty has a 3.27 ERA with 15 strikeouts and seven walks.
With a win on Saturday, the Blue Jays have the opportunity to clinch a post-season berth for the first time since 2023.