On the other side, Washington Nationals manager Blake Butera is sending Carson Palmquist to the mound, and that framing is generous. Palmquist's last five outings: 0.1 innings, 1.0 innings, 1.0 innings, 3.0 innings, 1.2 innings. That is 7.0 total innings across five trips to the hill. Whatever is driving those limits, whether pitch count restrictions, injury recovery, or roster management, this is not a starting pitcher in any traditional sense tonight. His 8.74 ERA in 2026 confirms what the inning logs already tell you: when hitters see him, they do damage, and they do it fast. Plan for him to be gone by the second or third inning.

The real game begins the moment Palmquist exits and the bullpen math takes over. Washington's relief corps carries a 5.20 ERA. Arizona's sits at 3.26. That is not a small gap. In a contest where Washington will need six or seven innings from its relievers, that structural mismatch is the defining edge of this matchup. The Diamondbacks are 8-2 over their last 10 games and riding genuine momentum. However, there is one counterweight worth respecting: Washington is 21-12 against left-handed starters this season. Rodriguez is left-handed. Butera's lineup, when facing a southpaw, has been among the better units in the league against that split. That is not a throwaway stat when the Nationals are playing within 1.5 games of a wild card spot.

Butera has acknowledged publicly that this team is embracing the pressure of meaningful baseball, and that context matters. A home team with wild card stakes, a favorable platoon split against tonight's starter, and a hostile crowd is not the same as a 20-31 home record implies. Arizona did travel from St. Louis after playing yesterday, a minor fatigue variable but real in a tight game. The outcome tonight hinges almost entirely on two questions: how quickly the Washington bullpen surrenders runs to a hot Arizona offense, and whether Rodriguez is pitching at full capacity or protecting something for September.

• Carson Palmquist has totaled just 7.0 innings across his last five appearances. This is a bullpen game for Washington starting in the second or third inning, regardless of how Rodriguez performs.
• Washington's bullpen ERA of 5.20 against Arizona's 3.26 creates a structural pitching edge that compounds across six or seven innings of relief work tonight.
• Eduardo Rodriguez is 8-3 with a 2.62 ERA in 2026, but his last three starts averaged only 3.67 strikeouts, and the July 19 implosion (2.2 IP, 5 ER) raises legitimate questions about fatigue or pitch-count management coming into tonight.
• Washington is 21-12 against left-handed starters this season. Rodriguez is a lefty. The Nationals lineup has a genuine platoon advantage that the market may be underweighting.
• CJ Abrams is 0-for-6 lifetime against Rodriguez with a 0.000 OPS across both his 2025 (3 PA) and 2026 (3 PA) samples. Ketel Marte, on the other side, is 2-for-5 with a 1.200 OPS against Palmquist.
• Nationals Park plays as a neutral venue with a runs factor of 1.0 and a home run factor of 1.02. No park effects skewing this game. The outcome comes down to pitching depth, not dimensions.

The best individual play tonight is the CJ Abrams Under 0.5 Hits at +140. A 0-for-6 career record against Rodriguez with a 0.000 OPS across two separate seasons is a real pattern, and getting plus money on it is durable value. The Diamondbacks ML at -135 is the main bet, supported by Arizona's momentum and the bullpen mismatch. The Under 9.5 depends on Rodriguez's health. If he pitches well, the under has legs. If he exits early, Washington's offense and its reliable production against lefties could push this total over. Size the under smaller and treat E-Rod's health as the key variable to track before first pitch.

For the full slate tonight, see our MLB picks today, NRFI picks, and player props.