From Chronicle Staff Writer Susan Slusser in Toronto

I’ve just had it confirmed: Tyson Ross is getting called up to join the A’s tonight in Toronto.

I had a feeling when Ross didn’t open the season on the roster that we’d see him in an Oakland uniform soon. Not quite this soon, sure, but the A’s never use just five starters over the course of a season. It’s not clear, though, if Ross will start. I’m told that tonight’s scheduled starter, Dallas Braden, is fine. But I’m not sure what that means, precisely.

UPDATE: ESPN’s Buster Olney is reporting that Braden is making his start tonight.

The only other issue I’m aware of with the pitching staff is in the bullpen, where Brian Fuentes has been unavailable for a few days with a blister on his left middle finger. He played catch yesterday and said it went well. He could be backdated on the DL only to Saturday, and that would be an awfully long time to be out with a blister, so I think that seems a little unlikely. Maybe there’s a mystery ailment somewhere, or maybe the A’s just want a fresh arm on the staff. My best guess – and it’s been a morning of guesswork – is that someone else has an injury that we haven’t heard about yet.

Braden was the logical assumption after his initially scheduled start was pushed back from last night to tonight, initially without any explanation, which seemed unusual. Braden told us yesterday that he was asked if he’d like an extra day to work on things and he jumped at it because he wanted to refine his slider, which he ditched in favor of a curveball briefly during the spring.

Braden’s last outing was the final game of the Bay Bridge series last Wednesday, and there’d been no hint of any physical issues. He went 5 2/3 innings and he looked very good.

This morning’s other A’s news: A stats service provided the A’s erroneous post-game info last night, and it turns out that the A’s nine errors in the first four games are indeed an Oakland record. The 1970 team made eight errors in the first four games, and 10 in the first five, if you’re looking for the number the A’s would like to avoid tonight. Thanks to David Feldman, king of A’s stats, for discovering the discrepancy and providing the right information, as he so often does. If you don’t already, follow him on @dfeldy.