The Pirates have signed right-hander Isaac Mattson to a minor league deal, according to his transactions tracker at MLB.com and relayed by the player himself on his Instagram page. He has been assigned to Triple-A Indianapolis for now but will presumably receive an invite to big league spring training.
Mattson, 29, signed a minor league deal with the Bucs for the 2024 season as well. He was selected to the roster in September and was able to throw 5 1/3 innings over three appearances, allowing three earned runs. He also got into four games with the Orioles in 2021, giving him a 5.59 ERA in seven major league games at this point in his career. He was outrighted off the roster at the start of the offseason.
That’s obviously not much of a sample size to make conclusions from, but the Bucs just got an up-close look at Mattson in Triple-A for most of the 2024 season. He tossed 60 innings over 29 appearances at that level with a 3.15 ERA. His 12.9% walk rate there was on the high side but his 29.8% strikeout rate was quite strong. That’s generally been the case for him at the upper levels of the minors. He has thrown 138 1/3 minor league innings over the past four years with a 4.10 ERA, 27.9% strikeout rate and 14.5% walk rate.
There’s no harm in a minor league deal, so the Bucs will bring him back in a non-roster capacity. If he can take a step forward in terms of control, that would obviously improve his utility. If he earns his way back onto the roster, he is still has two option years and has very little service time, meaning he can potentially be cheaply retained in a depth role for quite some time.