Yarbrough will cover the bulk of innings Wednesday against the Red Sox following opener Andrew Kittredge, Marc Topkin of the Tampa Bay Times reports.
Yarbrough was effective in the same role against the Blue Jays last Friday, allowing just one run across 5.1 innings while recording four strikeouts. The southpaw has similar numbers as a starter and reliever this season but has been slightly more effective as the latter, posting a solid 3.64 ERA, .218 BAA and .253 wOBA over 47.0 innings out of the bullpen.