What you need to know about MLB’s roster deadlines

Blue Jays TV voice Buck Martinez thinks GM Ross Atkins is still very active on the trade front, but says he still thinks they can get to the World Series without another lefty specialist in the bullpen.

BALTIMORE – As August gives way to September, baseball’s calendar starts to shift gears. This time of year the summer grind becomes the stretch run.

Or, as Toronto Blue Jays manager John Gibbons put it: "there’s not a lot of games left, but there’s a lot of games left.”

August 31 marks a turning point on a couple of fronts: it’s the last day to add players with post-season eligibility and it’s the final day before rosters expand.

Here’s some context on some potentially confusing rules…

LAST DAY TO ADD PLAYOFF-ELIGIBLE PLAYERS
Players are only eligible for playoff rosters if they’ve stayed in the same organization since August 31. That typically leads to a flurry of modest moves around the big leagues as general managers look to round out their rosters. For example, Coco Crisp would be eligible for Cleveland’s playoff roster because he was acquired in August.

The Blue Jays could have interest in trading for a left-handed reliever or left-handed bench bat before the clock strikes midnight. Realistically it’s tough to pull off an impact trade this time of year, since players have to be placed on waivers before being traded.

At the very least, the Blue Jays are expected to pursue a new deal with catcher Josh Thole, who was recently granted free agency. As long as Thole re-joins the organization in August, he’d be playoff eligible (he doesn’t need to be on the roster).

CALL-UPS ON THE WAY
Rosters expand from 25 to 40 in September, allowing teams to add to their bullpens and benches. The Blue Jays expect to call a few players up Friday when they open a series against the Tampa Bay Rays and then add more players later in the month after the triple-A season ends.

TRADES STILL POSSIBLE
Teams are still free to make trades in September, but those acquisitions aren’t eligible to play in the post-season. For example, Darwin Barney helped the Blue Jays down the stretch last year even though he was ineligible for the playoffs.

Generally speaking, though, if you’re acquiring a player in September it’s either a marginal upgrade or you’re scrambling because of something unexpected.

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