Runzler appeared in eight games out of the bullpen for the Pirates in 2017, allowing two runs on seven hits while fanning four over four innings. While he's spent the majority of his time in the minors of late, his major-league experience is certainly a perk for the Red Sox. Runzler will likely serve as organizational depth at Triple-A Pawtucket to start the 2019 campaign.

Runzler delivered scoreless outings in four of his five Grapefruit League appearances with the Rays, but with an Opening Day bullpen spot not in the offing, the left-hander likely requested to be let go. The 32-year-old, who split his 2017 campaign between the Pirates and their Triple-A affiliate at Indianapolis, will look to find work elsewhere with a team in need of a lefty reliever.

Runzler made eight appearances for the Pirates last year, striking out four batters and allowing two home runs over the course of four innings. It was his first major-league action since 2012. He's spent the majority of the past five seasons pitching in Triple-A, where he's had an xFIP north of 4.20 in each season. The veteran left-hander will look to earn a spot in the Rays' bullpen but doesn't look to be a favorite to secure a roster spot.

The 32-year-old southpaw decided to refuse his outright assignment to Triple-A Indianapolis, making him eligible to sign anywhere he pleases. Runzler made his first major-league appearance since 2012 last season, compiling a 4.50 ERA and 4:2 K:BB across four innings with the Pirates. At this point in his career, Runzler doesn't figure to serve as anything more than organizational depth.