First Pitch: A dark horse World Series threat exposed themselves in the desert

The Arizona Diamondbacks began the month of June on a five-game losing streak and with a 25-32 record overall. They were hanging around in the NL Wild Card race with most of the league struggling to pull away, but were nowhere near the team that wrapped up the NL Pennant eight months prior.

The Diamondbacks won their first game in June in dominant fashion, and haven't slowed down. They've gone 41-21 since, and are now 66-53 on the season after taking three of four at home against the Philadelphia Phillies.

The Diamondbacks have been playing elite baseball for months, and have won 15 of their last 18 overall. Not only are they tied with the San Diego Padres for the top Wild Card spot in the National League, but they're only 3.5 games back of the first-place Los Angeles Dodgers in the NL West. At the end of May, they were 10.0 games back of first place and had slim odds to make the postseason.

The Diamondbacks are peaking at the right time and the scary thing is, they might only just be getting started. Arizona looks as formidable as any team in the National League, and should be considered a true World Series contender for several reasons.

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The Diamondbacks should only improve as their rotation takes shape

The Diamondbacks entered this season expecting to have one of the best starting rotations in the majors, but it hasn't played out that way. As of this writing, they rank 25th in the majors with a 4.66 starting pitching ERA, and 22nd in innings from their starters. That's nowhere near expectations, but there are reasons to believe it can and will get much better.

First, and most obviously, the Diamondbacks haven't been healthy all year. Eduardo Rodriguez just made his season debut five days ago, giving up three runs in 5.2 innings in a win over the Cleveland Guardians. Merrill Kelly made his fifth start of the year and his first since April 15 on Sunday, delivering five innings of two-run ball. Zac Gallen and Jordan Montgomery have missed time as well.

Speaking of Montgomery, even he has looked a bit better. He allowed one run in a rain-shortened start in Pittsburgh two starts ago, and his last time out saw him pitch better than his final line suggested. Montgomery held the Phillies off the board through five innings. They finally scored against him in the sixth, but three of the four runs he wound up allowing were driven in against Dylan Floro, the pitcher who relieved him with two outs in the sixth. Montgomery allowed four runs in 5.2 innings, but he was one pitch away from a quality start against the Phillies.

They're healthier now than they have been all season, and are even seeing younger pitchers emerge. 25-year-old Brandon Pfaadt has been inconsistent for much of this season but he has a 2.66 ERA in his last seven starts. 26-year-old Ryne Nelson looked like nothing more than a depth starter, but he has a 2.90 ERA in his last eight appearances (seven starts). The Diamondbacks have won every single start he has made in that stretch, and he has averaged over six innings per outing. He has pitched so well to the point where Arizona cannot remove him from the rotation.

The Diamondbacks are where they are despite having one of the worst rotations in the majors statistically. With everyone healthy and kicking things into gear, there's reason to believe it can be one of the league's best. A rotation featuring Gallen, Kelly, Rodriguez, and Pfaadt with Montgomery and Nelson as insurance is really tough to beat.

Corbin Carroll is showing signs of life for an already dynamic offense

While their pitching has had its struggles, Arizona has had one of the best offenses in the majors for much of the season. Ketel Marte, a bonafide NL MVP candidate, is leading the way, but their lineup is as deep as any.

The Diamondbacks lead the majors in runs scored. They're tied for seventh in the majors in home runs. They're 15th in the majors in stolen bases. They're first, third, and eighth in those categories since June 1, proving they can beat you with the longball and with their legs. Corbin Carroll has been right in the middle of that.

Carroll had an absurd rookie year, winning the NL Rookie of the Year award while being one of, if not the best player on the eventual NL Champions, but he took a major step back to begin this season. He was slashing .213/.305/.315 with just two home runs and 14 stolen bases through the end of June.

Since the calendar flipped to July, Carroll has rediscovered his power stroke. He's hitting just .231 in the 33 games he's appeared in since July 1, but has hit nine home runs in those 121 at-bats, and has gone yard in back-to-back games for the first time since July 22-23 of last season. He has stolen seven bases in just over a month as well.

He isn't performing like he did in the first half of 2023, but this is about as well as he's played since then. A rejuvenated Carroll alongside the likes of Marte, Christian Walker, Joc Pederson, and Lourdes Gurriel Jr. is a frightening sight for the competition.

The Diamondbacks' bullpen is better now than it has been all season

The Diamondbacks didn't make a splash at the trade deadline but made sure to address the weakest link of this team, the bullpen. The Diamondbacks rank 22nd in the majors with a 4.23 ERA and are tied for the fifth-most blown saves in the majors with 21. Things had gone so poorly for Paul Sewald in particular to the point where he was recently taken out of the closer role.

They gave up a ton, but got A.J. Puk, a controllable left-handed reliever who has immediately stepped up and been lights out for them. Puk had been dominant in relief for the Marlins before the trade, and despite giving up a couple of back-breaking hits, he has allowed just one run in 6.2 innings of work as a Diamondback, issuing one walk with 11 strikeouts while working primarily in the eighth inning.

Things haven't gone as well for the other reliever they acquired, Dylan Floro, but based on how well he pitched for Washington earlier this season, there's reason to believe he'll be fine as a middle reliever.

Adding Puk and Floro to a bullpen consisting of breakout 23-year-old Justin Martinez, funky right-hander Ryan Thompson, and Sewald who was great for them in October last season, can potentially turn the 'pen from a weakness into a strength. At the very least, the 'pen looks way better on paper than it did before the deadline, and should have enough talent to close games led by their rotation and dynamic offense.

This Diamondbacks team is as stacked as any in the National League. They have star power, depth, and the experience to give fans a reason to expect another deep run in the postseason.