The Giants filled a hole in their bullpen with a unique pitcher on Tuesday, signing right-handed reliever Matt Wisler to a 1-year, $1.15 million deal, according to Ken Rosenthal of The Athletic.

Wisler was non-tendered by the Minnesota Twins ahead of the Rule 5 Draft, a move that some considered a surprise.  With the Twins in 2020, the 27-year old had a 1.07 ERA in 18 appearances (25.1 innings), with 35 strikeouts and 14 walks.  Wisler actually allowed a higher batting average allowed to right-handed batters (.190) than left-handers (.121) in 2020.

The season was a breakout for Wisler, who had struggled in the past.  He had a 5.61 ERA in 44 appearances in 2019, split between the San Diego Padres and the Seattle Mariners.  His lowest season ERA before 2020 was a 4.28 ERA in 2018 between the Atlanta Braves and the Cincinnati Reds.

The notable thing about Wisler is that in 2020 he threw his slider an incredible amount, 83% of the time.  Opponents hit just .143 off the pitch, and had a total of just three extra-base hits off of it.  That earned comparisons by some after this signing to Sergio Romo, whose successful run with the Giants through their World Series years was fueled by his extensive use of a no-dot slider, with which he struck out Miguel Cabrera to end the 2012 World Series among many other strikeout victims.

Wisler uses the slider to work off a 92 mph fastball, much slower than many relievers.  But if he keeps his 2020 form, his ability to master both left-handed and right-handed batters will be an advantage in the late innings for the Giants.