After posting a combined winning percentage of less than 40% over the last three seasons, the Arizona Diamondbacks were far from favorites in the NL West entering the 2023 MLB season. The Los Angeles Dodgers and San Diego Padres had the star power to contend for a World Series, while the San Francisco Giants had the pitching to stay in contention.

As for Arizona, the Diamondbacks had a lot of speed, two great starting pitchers, and little else. Yet through the first two months of the season, the ballclub is 31-23 — holding down the top NL Wild Card spot and sitting just 1.5 games back from the Dodgers.

Rookie Corbin Carroll has been phenomenal, veterans Christian Walker and Ketel Marte have held down the middle of the order, while right-handers Zac Gallen and Merrill Kelly have carried the starting rotation. But the Diamondbacks still have multiple areas available for improvement.

Arizona has been unable to find a consistent third outfielder, and the team seriously lacks pitching depth. Looking at the first third of the season, which disappointing Diamondbacks have frustrated fans the most during 2023?

3 Diamondbacks players fans are already fed up with in 2023

Jake McCarthy

After finishing fourth in NL Rookie of the Year voting last season, Jake McCarthy has hardly looked like the player that posted a 2.4 WAR in just 99 games played in 2022. McCarthy's batting average is down from .283 to a paltry .162 which prevents him from utilizing his biggest asset: speed.

McCarthy ranks in the 98th percentile in spring speed per Baseball Savant and stole 23 bags as a rookie. It's hard to steal bases when you're not getting on base. Some of the outfielder's struggles can be attributed to bad luck. McCarthy is batting just .190 on balls in play (.300 is the MLB average) and his expected batting average is a more respectable .237.

His other advanced stats, like expected slugging, are also in line with the numbers he posted in 2022 — suggesting that Jake McCarthy should rebound after returning from a short stint back in Triple-A.

Brandon Pfaadt

Between Zac Gallen and Merrill Kelly, the Diamondbacks offer two of the best starting pitchers in Major League Baseball at the top of their rotation. The rest of the Arizona rotation has hardly even been MLB quality.

If Madison Bumgarner (10.26 ERA in four starts) was still on the team, he would have been the obvious scapegoat here. But the Diamondbacks released the veteran lefty in April. This leaves a trio of youngsters in Ryne Nelson, Tommy Henry, and Brandon Pfaadt. Of these three, Pfaadt is the most promising and has also struggled the most.

Pfaadt was the #59 prospect in Major League Baseball entering the 2023 season — making him the Diamondbacks' third-ranked minor-leaguer. Pfaadt posted a combined 218 strikeouts in 2022 with Arizona's Double-A and Triple-A affiliates to go with a 3.83 ERA.

His minor league success has not carried over to the majors. Pfaadt gave up eight home runs in five starts, allowing 22 earned runs in total across 23.2 innings pitched. He ranks in the 3rd percentile in expected ERA and his expected slugging allowed is the fourth worst in MLB. Brandon Pfaadt lasted less than a month before Arizona demoted him to the minors.

Scott McGough

Few baseball players can offer a more interesting path to the majors than Scott McGough. McGough pitched 6.2 innings for the Marlins in 2015 before returning to the minors. He spent 2019-2022 playing in Japan, where he was a lockdown closer for the Yakult Swallows.

The 33-year-old's season began with promise, as he earned his first MLB save on April 2, but since then McGough has blown three saves in four opportunities, resulting in an 0-4 record. The veteran has been better of late, with an ERA of 0.73 over his last 12 appearances, although most have come in lower-leverage situations.

Fans hate relievers who cough up leads, and it is hard to see Diamondbacks supporters regaining trust in Scott McGough.