Bubba Chandler and Eduardo Rodríguez Set for Opening Matchup as Pirates Visit Diamondbacks

Key facts

• Pittsburgh Pirates (19-16) travel to Arizona Diamondbacks (16-17) for a three-game series starting Tuesday, May 5, 2026 at 9:40 p.m. EDT.
• Pirates starter Bubba Chandler (1-3, 4.97 ERA) leads the NL with 20 walks; Diamondbacks starter Eduardo Rodríguez (2-0, 3.03 ERA) has a 3.03 ERA but ranks in the 26th percentile in expected ERA.
• Arizona has lost seven of its last 10 games, including a sweep by the Chicago Cubs; Pittsburgh swept the Cincinnati Reds in its previous series.
• Diamondbacks hitters rank seventh in the NL with a.247 batting average; Pirates hitters rank fourth at.253.
• Oneil Cruz leads the Pirates with nine home runs and a.500 slugging percentage; Corbin Carroll leads Arizona with seven doubles, four triples, four home runs and 18 RBIs.
• Arizona's rotation ERA ranks last in the majors; its bullpen ERA ranks seventh-worst.
• Pirates relievers (minimum 10 games) all have positive WAR except one.

A Tale of Two Trajectories

The Pittsburgh Pirates and Arizona Diamondbacks open a three-game series at Chase Field on Tuesday night, each carrying a record that tells only part of the story. Pittsburgh sits at 19-16, fourth in the National League Central but with a run differential that suggests a 20-15 team. Arizona, at 16-17, has a run differential that points to a 14-19 mark, dragged down by lopsided losses to the Milwaukee Brewers last week. The Pirates arrive fresh from a sweep of the Cincinnati Reds, while the Diamondbacks were themselves swept by the Chicago Cubs over the weekend. The divergence in momentum mirrors deeper structural differences between the two clubs.

Pitching Probables: Chandler vs. Rodríguez

Bubba Chandler, a 23-year-old right-hander, will make his seventh start of the season for Pittsburgh. His 4.97 ERA and 1.48 WHIP belie flashes of the promise he showed in 2025, but control remains a persistent issue: his 20 walks lead the National League. Chandler has allowed at least three earned runs in four of his six starts, including six in a road outing against the Texas Rangers on April 23. Opposing him is veteran left-hander Eduardo Rodríguez, who has defied his recent struggles to post a 3.03 ERA through five starts. Yet advanced metrics are less kind: Rodríguez ranks in the 26th percentile in expected ERA and below the median in nearly every Statcast category except hard-hit rate (52nd percentile) and ground-ball rate (51st). His inability to generate chases or whiffs could neutralize some of Pittsburgh's offensive weaknesses, particularly against left-handed pitching.

Offensive Strengths and Weaknesses

The Pirates have the fourth-best team batting average in the National League at.253, a marked improvement from last season when they finished dead last in OPS. Infielder Brandon Lowe has emerged as one of the offseason's shrewdest acquisitions, while rookie Konnor Griffin is beginning to hit consistently. Oneil Cruz leads the team with nine home runs and a.500 slugging percentage; Nick Gonzales has gone 16-for-39 with two doubles and six RBIs over the last 10 games. Arizona's lineup, by contrast, has regressed offensively. After ranking fifth in OPS last season, the Diamondbacks have dropped to 11th, a decline partly attributed to the trade of Josh Naylor and Eugenio Suárez at last summer's deadline. Corbin Carroll remains a bright spot with a.273 average, seven doubles, four triples, four home runs and 18 RBIs, but Geraldo Perdomo and Ketel Marte have started slowly, and Lourdes Gurriel Jr. has been worth negative WAR in his return from a torn ACL.

Bullpen and Depth: A Key Disparity

Pittsburgh's pitching staff, a strength last season, has been maintained with remarkable consistency. Every Pirates starter and all but one reliever (minimum 10 games) have recorded positive WAR. The bullpen, in particular, has been reliable, a factor that could prove decisive in a series where both starters are expected to work five or six innings. Arizona's pitching, however, has not improved. The Diamondbacks' rotation ERA ranks dead last in the majors, and their bullpen ERA ranks seventh-worst. The team's injury list is extensive: Carlos Santana (groin), Jordan Lawlar (wrist), Tyler Locklear (elbow), A.J. Puk (elbow), Blake Walston (elbow), Andrew Saalfrank (shoulder), Cristian Mena (shoulder), Corbin Burnes (elbow), Pavin Smith (elbow) and Justin Martinez (elbow) are all on the injured list, with several on the 60-day IL.

Matchup Dynamics and Predictions

Chandler's struggles with walks and ground-ball rate (17th percentile) are mitigated by Arizona's tendencies: the Diamondbacks have drawn the second-fewest walks in the majors and hit grounders at the 10th-highest rate. Chandler ranks within 10 percentiles of the league median in several Statcast categories and has limited hard contact, which could trouble a Diamondbacks lineup that has produced a lot of soft contact this season. Rodríguez, meanwhile, has been better on the surface than underlying numbers suggest. His low strikeout and high walk rates could play into Pittsburgh's hands, though the Pirates have been significantly worse on the road, posting the third-worst road OPS in baseball. The veteran lefty should be able to pitch deeper into the game, keeping the ball away from a bullpen that has been Arizona's Achilles' heel.

Stakes and Outlook

For Pittsburgh, this series is an opportunity to solidify its position in a fiercely competitive NL Central, where even a 19-16 record places them fourth. The Pirates have the run differential of a 20-15 team and have shown improvement on both sides of the ball. A strong showing on the road could build momentum as they face a Diamondbacks team that has lost seven of its last 10 games. Arizona, meanwhile, is under pressure to reverse a slide that has seen them fall below.500. The Diamondbacks' pitching staff, already depleted by injuries, must find a way to contain a Pirates lineup that is finding its stride. With the trade deadline still months away, the series opener offers an early test of whether Arizona can arrest its decline or whether deeper structural issues will persist.

The Verdict: A Clash of Inconsistency

Both teams enter Tuesday's game with more questions than answers. Chandler has the raw stuff but lacks control; Rodríguez has the results but not the underlying performance. In such a matchup, the bullpen often decides the outcome, and here Pittsburgh holds a clear advantage. The Pirates' relievers have been uniformly effective, while Arizona's have been a liability. If Chandler can limit walks and work efficiently into the fifth or sixth inning, Pittsburgh's bullpen should be able to close out a tight game. The Diamondbacks, by contrast, will need Rodríguez to pitch deep and hope their offense can capitalize on any mistakes. In a series that could set the tone for both teams' trajectories, the opening game may come down to which starter can best manage his own limitations.

The bottom line

• Pittsburgh Pirates (19-16) have a run differential of a 20-15 team and swept the Reds; Arizona Diamondbacks (16-17) have a run differential of a 14-19 team and were swept by the Cubs.
• Bubba Chandler leads the NL in walks (20) but faces a Diamondbacks lineup that draws the second-fewest walks in MLB.
• Eduardo Rodríguez has a 3.03 ERA but ranks in the 26th percentile in expected ERA and below median in most Statcast categories.
• Arizona's rotation ERA is the worst in baseball; its bullpen ERA is seventh-worst; Pittsburgh's relievers (except one) all have positive WAR.
• The Diamondbacks have 10 players on the injured list, including key contributors like Corbin Burnes and Carlos Santana.
• Pittsburgh has the third-worst road OPS in baseball, but Arizona's pitching weaknesses could offset that disadvantage.