The final spots of the St. Louis Cardinals' major league roster have drawn a lot of eyes and discussion this spring.

The Cardinals spent most of the last year building assets for the future and have put together the first stage of a rebuilt roster. The hopes are that many of the players currently with St. Louis prove to be foundational pieces for the future. Due to the Cardinals still being towards the beginning of a top-to-bottom rebuild rather than the end, it's likely that the organization will get a look at several intriguing and promising prospects.

One of those prospects seems to be right-handed pitcher Luis Gastelum.

Gastelum, who competed for Mexico in the 2026 World Baseball Classic, was reassigned to minor league camp recently. However, he seemed to make enough improvements to put himself on the organization's major league radar according to a post on "X" from Belleville News-Democrat reporter Jeff Jones.

According to Jones, Gastelum was "no doubt" the prospect that made the biggest improvement from "name on a page" to a player who could legitimately make a big league impact this year.

Gastelum, who's ranked as the organization's 22nd-best prospect according to MLB Pipeline, was signed by the team as an international free agent out of the Mexican Leagues on April 26, 2023.

Gastelum has participated with the major league camp the last two springs in some capacity. He's totaled seven outings across his pair of springs, including four this year.

This time around, Gastelum had a 0.00 ERA in Grapefruit League competition and struck out six batters in four innings pitched. He didn't allow a hit and allowed just one free base via a walk.

Gastelum spent all of last season with St. Louis' Double-A affiliate, the Springfield Cardinals. He had a 4.02 ERA and fanned 92 batters in 46.2 innings pitched across 46 appearances.

Across his three seasons in the Cardinals farm system, Gastelum has recorded a solid 3.66 ERA with 191 strikeouts across 140 innings pitched 96 appearances.

Currently, St. Louis is predicted by FanGraphs roster resource page to begin the season with a bullpen of: right-hander Matt Pushard (long-relief), right-hander Chris Roycroft (middle leverage), right-hander George Soriano (middle leverage), left-hander Justin Bruihl (middle leverage), right-hander Ryne Stanek (closer), right-hander Matt Svanson (closer), left-hander JoJo Romero (closer) and right-hander Riley O'Brien (closer).

Based on Jones' report and the spring he had, it's reasonable to assume Gastelum's call-up will be sooner rather than later.

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