Five biggest moves that put Rangers, Diamondbacks on World Series trajectory

Just a year ago, the fourth-place Rangers and Diamondbacks finished 38 and 37 games back in their respective divisions. Needless to say, it took some prudent roster moves to get them where they are now. 

The Rangers trusted they had the offensive pieces necessary and turned to free agency to bolster both their rotation and their coaching staff, convincing three-time champion Bruce Bochy to end his short retirement and take the reins in Texas. The D-backs believed in their youth, hoping another year of development for burgeoning superstar Corbin Carroll and company could make them competitive.

With the playoffs in sight, both teams pushed the right buttons at the deadline to push them over the edge. 

These are the five biggest roster moves Texas and Arizona made since the end of last season to put them on their World Series path. 

5) Rangers call up top prospect Evan Carter (Sept. 8, 2023) 

As much as the Rangers' massive spending the past two offseasons contributed to where they are now, their first playoff berth since 2016 wouldn't have been possible without help from their farm system. A plethora of young talents made a massive leap in 2023. 

After missing much of last season due to a torn labrum, Josh Jung had a normal offseason to train instead of rehab, and the Rangers' 2019 top selection proceeded to finish tied for fifth in homers and sixth in doubles among all qualified rookies despite missing most of August and September with a fractured thumb. Beyond that, versatile 24-year-old Ezequiel Duran provided crucial coverage in the wake of infield injuries throughout the season while Leody Taveras solidified the center field spot in a career year. 

But none provided a spark quite like Carter. 

In early September, Jung was still out with his thumb injury, Adolis García was sidelined with a knee injury, and the Rangers had fallen to third place in the American League West. Their decision to call up their 21-year-old top prospect might have saved the Rangers' season.

Carter posted a 1.059 OPS with the lowest chase rate in baseball over a small sample in September, taxing pitchers and lengthening an already deep Texas lineup with his remarkable plate discipline. In his 23 games played, only four major-leaguers were worth more wins to their team. 

That production has continued into his first postseason. Carroll will almost certainly win National League Rookie of the Year honors and came up huge in Arizona's Game 7 to best the Phillies, but both Carter (.987) and Jung (.920) have a higher OPS this postseason than the Diamondbacks' star outfielder. The Rangers' duo is just the third pair of rookie teammates in MLB history to tally 10 hits apiece in a single postseason. 

4) Diamondbacks acquire Paul Sewald from Mariners for Josh Rojas, Dominic Canzone and Ryan Bliss (July 31, 2023)

It seemed like the Rangers might have added the best reliever available leading into the deadline when they traded for Aroldis Chapman, but the Diamondbacks one-upped them in a bullpen move that will help them both this season and next. 

Arizona was in the market for starting and relief help and went with the latter, acquiring Sewald from the Mariners. It was a necessary move for the D-backs to compete this year considering their revolving door at closer throughout the season's first half. Seven different relievers had at least one save attempt and three had at least nine chances before the All-Star break. 

Sewald solidified the spot to help keep Arizona in the playoff mix. While he wasn't exactly flawless after the trade, he has been pristine in October, going 6-for-6 in save opportunities. No other MLB reliever has more than three saves this postseason. 

Sewald's ability to stabilize the ninth has allowed manager Torey Lovullo to confidently deploy the matchups he wants ahead of him, which has been crucial for a D-backs team with little reliable rotation depth behind Zac Gallen and Merril Kelly. Sewald and setup man Kevin Ginkel have combined to throw 17 scoreless innings in relief this postseason, turning what was a deficiency for the franchise into one of its strengths. 

3) Diamondbacks acquire Gabriel Moreno and Lourdes Gurriel Jr. from Blue Jays for Daulton Varsho (Dec. 23, 2022)

Many praised Toronto after this offseason trade went down — *raises hand* — for adding what seemed to be the missing piece to the Blue Jays' outfield. Instead, the early returns suggest a massive win for Arizona. 

Though Varsho's defense came as advertised, his offense regressed. Meanwhile, Gurriel illustrated an All-Star season while Moreno took the leap he wouldn't have been able to in Toronto. The Diamondbacks' catcher of the future is producing in the present, already demonstrating himself to be among the best defensive backstops in the game at 23 years old. 

With the addition of Moreno, a speedy Arizona club that was already one of the most dangerous teams on the bases also became one of the best at controlling the running game. Moreno has one passed ball in more than 1,000 innings behind the plate the past two years and boasts one of the fastest pop times in baseball, as evidenced by the majors' best caught stealing rate this season. 

And he has some pop at the plate, too. 

While he was a league average bat during the regular season, his offense has skyrocketed at the most important time of year. Moreno ranks behind only the Dodgers' Will Smith for the highest OPS from a catcher this postseason (.852, in about four-times the plate appearances as Smith). Moreno homered once in the wild-card series, twice in the NLDS and batted .296 in the NLCS. 

The D-backs' stunning upset of the Phillies had the newcomers' fingerprints all over it. 

In Game 6, as the series returned to Philadelphia, deadline acquisition Tommy Pham and Gurriel quieted the home crowd with back-to-back bombs to start the scoring. And in Game 7, Moreno produced the go-ahead hit that would allow Arizona to return to the World Series for the first time since winning it in 2001. 

2) Rangers acquire Jordan Montgomery and Chris Stratton from Cardinals for John King, Tekoah Roby and Thomas (July 30, 2023)
1) Rangers sign Nathan Eovaldi (Dec. 27, 2022)

Both pivotal Texas pitching additions were overshadowed at the time by another flashier move. 

Jacob deGrom was the Rangers' prized offseason move, while Max Scherzer was the headliner at the deadline. But DeGrom underwent Tommy John surgery in June, Scherzer suffered a teres major strain in September, and Eovaldi and Montgomery solidified the Texas rotation in their stead. 

Eovaldi, the last piece added to the Rangers' rotation reboot this offseason, was also their most important.

The same day deGrom went to the injured list, Eovaldi spun the first nine-inning shutout of his career. He finished the first half 10-3 with a 2.83 ERA, and while his full 2023 numbers took a dip as he built his way back from a summer forearm strain, he did what was necessary to put himself in position to contribute in October, where he tends to find another level. 

Eovaldi is 4-0 with 28 strikeouts and four walks in four starts this postseason. If he wins his Game 1 outing against the Diamondbacks on Friday (8:03 p.m. ET, FOX and the FOX Sports App), he'll join Randy Johnson (2001), Francisco Rodríguez (2002) and Stephen Strasburg (2019) as the only pitchers with at least five wins in a single postseason. Eovaldi would be the only pitcher from that group to have started all five of those wins. 

Given the nature of his injury, it was far from a guarantee Eovaldi could return to this level before season's end. Uncertain about his health in July, and needing another starter to rely on, the Rangers sought rotation help at the deadline, acquiring Scherzer from the Mets and Montgomery from the Cardinals. The former was productive when healthy; the latter was essential. 

With the Rangers fighting for a playoff spot, Montgomery wrapped up his 2023 regular season campaign allowing just two runs over his final four starts (27 innings) in Texas. He carried that momentum into October, where he posted a 2.38 ERA over four starts before delivering 2.1 scoreless innings of relief on two days of rest in the Rangers' Game 7 ALCS win in Houston. 

The Rangers' top pitching duo has started eight of their 12 games this postseason, combining for a 2.29 ERA in 51 innings; the rest of the Rangers pitching staff has combined for a 4.89 ERA in 57 innings, including a 9.00 ERA from Scherzer and Andrew Heaney.

As much as the Rangers' offense carried them into the postseason, Montgomery and Eovaldi have put them in position to claim their franchise's first World Series title.

Rowan Kavner covers the Dodgers and MLB as a whole for FOX Sports. He previously was the Dodgers' editor of digital and print publications. Follow him on Twitter at @RowanKavner.