When the Cardinals sent Luke Voit to the Yankees last season, Giovanny Gallegos was not seen as the key piece coming back to St. Louis.

That was supposed to be Chasen Shreve, a dependable lefty to help with the Cards' playoff run. He was fine down the stretch, pitching to the tune of a 3.07 ERA in 20 games last season. But at the beginning of the 2019 season, the Cardinals didn't have a spot for Shreve on their roster.

It was really starting to look like head-scratcher of a trade when Voit continued to mash for New York at the beginning of 2019, and Shreve and Gallegos couldn't crack the opening day roster for St. Louis.

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Now, in just a few months, Gallegos has turned himself into the Cardinals' most consistent bullpen option.

At the time of this writing, in his last 26 innings, Gallegos has only allowed two earned runs.

Overall on the season, Gallegos holds a 2.31 ERA in 46.2 innings.

His impressive numbers have also equated to an ascent in the pecking order for high leverage situations.

In those past 26 innings (21 games), Gallegos has only entered a game five times where there was a three run gap or more in the score. The Cardinals are saving him for the high pressure spots.

Gallegos has the lowest ERA and WHIP of any Cardinals pitcher with at least two innings pitched this season.

While guys like Andrew Miller (3.86 ERA), Dominic Leone (7.16 ERA) and Jordan Hicks and Alex Reyes (Injuries) were expected to anchor the bullpen at the beginning of the season, it's been guys like Gallegos, John Brebbia and John Gant that have ended up leading the way.

What's really made Gallegos successful are his strikeout and walk numbers.

The 27-year-old righty from Mexico has 67 strikeouts to just eight walks so far this season. His walk rate per nine innings pitched is tied for lowest on the team with Miles Mikolas at 1.5, and he's second highest on the team when it comes to strikeouts per nine innings pitched, with a 12.9 average. (Andrew Miller has the highest at 13.5.)

So the next time you find yourself wishing Luke Voit was still a Cardinal, just remember, the redbirds got a shut down reliever in return.