Saves are like pitcher wins and losses. They don’t really identify who’s a good or bad relief pitcher. Sometimes, bad relief pitchers can rack up a handful of saves, and the best relief pitcher doesn’t always get the chances to save games.
In 2002, the single season save record in Pittsburgh Pirates franchise history was set at 46, breaking the previous record of 33 set by Jim Gott in 1988. That record was set by right hander Mike Williams.
Williams wasn’t an absolutely dominant relief pitcher like you think he would be. In 61.1 innings, the closer had a 2.93 ERA, 3.91 FIP and 1.22 WHIP. Williams only struck out 16.1% of the batters he faced, but had a walk rate of 8.1%. His home run rate of 0.88 was solid, but not overly impressive. This is shown in his FIP and 3.99 xFIP.
His 0.4 fWAR isn’t great either. These numbers aren’t awful, but I’m sure if you were presented with them, you wouldn’t have guessed they came from a season where Williams posted a top 50 save total season.
Williams might also own the worst season by a National League All-Star. The following year in 2004, Mike surrendered 26 earned runs in his first 37.1 innings, and walked more batters than he struck out with a 20/22 BB/K ratio. Despite this, he still made the All-Star game, possibly because of his saves total. Eventually, he was traded to the Phillies for Frank Brooks.
The record was eventually broken by Mark Melancon in 2015 with 51 saves. He put up a truly dominant season for the Bucs with a 2.23 ERA, 2.82 FIP and 0.92 WHIP.