The other reliever that is returning from a rather serious injury is Nick Burdi. Burdi is in a very similar boat as Santana, although not coming off Tommy-John surgery. The Pittsburgh Pirates picked up Burdi in a rule v trade with the Philadelphia Phillies, who selected him from the Twins in the 2017-18 offseason. The Phillies picked him with the first overall pick in the rule v draft before flipping him to the Pirates for International bonus money.
Like Santana, Burdi showed a lot of promise in his big league debut. He opened the 2019 season as one of the last men out of the bullpen but quickly showed the stuff to earn a bigger role. He was throwing his fastball in the mid-90s and was showing off a really sharp slider that was generating a lot of swings and misses.
Overall his numbers look poor due to a small sample size and the injury that eventually sidelined him for the 2019 season. He only threw 8.2 innings and had an ERA over 9.00, but his FIP and xFIP were both under 3.00, suggesting he was pitching much better than what the box score was showing. The most impressive thing was that he struck out 17 batters in his 8.2 innings of work while only walked three.
On April 22nd Burdi pitched in his final game of the 2020 season. He only made it through 0.1 innings and gave up five earned runs. Then it happened. Burdi was seen on the mound grabbing at his right bicep in a lot of pain. It later came out that he tore his bicep from the bone and would miss the remainder of the season, although the injury is not viewed as significant of an injury as Tommy-John.
The Pittsburgh Pirates expect that Burdi is healthy and ready to go for the start of spring. In an interview, he made comment on how this was something that was bothering him for a while but was misdiagnosed by the Twins medical team. Hopefully, he is ready to go and is back to full health.