Seattle Mariners vs Washington Nationals Starting Lineup — Saturday, Jun 13, 2026

Seattle Mariners at Washington Nationals (2026-06-13). Luis Castillo vs Cade Cavalli at Nationals Park.

Luis Castillo enters this matchup with a season ERA of 5.16 and a WHIP of 1.36 across 61 innings pitched in 11 starts, demonstrating a K/9 rate of 9.0 and a BB/9 of 3.39. His recent performance indicates an alternating pattern with a downward trend in ERA, but also a high blow-up rate of 33.3 percent and a low quality start percentage of 16.7 percent. Over his last five outings, Castillo has shown significant inconsistency, ranging from 0 earned runs over 6 innings against the Yankees to 7 earned runs in just 3.1 innings versus the Astros, highlighting a volatile recent stretch. Cade Cavalli, for the Nationals, has posted a more favorable season ERA of 3.88 and a WHIP of 1.44 through 69.2 innings across 14 starts, with a K/9 of 9.82 and a BB/9 of 3.23. Cavalli's metrics suggest a stable pattern with a flat ERA trend and a zero percent blow-up rate, though his quality start percentage mirrors Castillo's at 16.7 percent. His recent starts include a 6-inning, 1-earned-run performance against the Phillies, but also a short 1.1-inning, 4-earned-run outing versus the Pirates, indicating some variability in his ability to pitch deep into games.

The Seattle Mariners' offense has generated 307 runs with a collective OPS of 0.719, driven by 93 home runs, indicating a moderate power threat. Their pitching staff, however, stands out with a strong team ERA of 3.57 and a WHIP of 1.18, alongside an 8.67 K/9 rate, allowing only 69 home runs. This suggests a pitching-reliant team. Conversely, the Washington Nationals' offense has been more productive, scoring 374 runs with a higher OPS of 0.739, hitting 91 home runs. The Nationals' pitching staff presents a stark contrast, holding a team ERA of 4.74 and a WHIP of 1.39, with a lower K/9 of 7.72 and having surrendered 101 home runs, suggesting a more susceptible unit on the mound.

Recent head-to-head contests from May 2025 between these two clubs featured elevated scoring, with the Nationals securing victories by scores of 9-3 and 9-0, while the Mariners took one game 9-1. These outcomes suggest a propensity for offenses to break through. The current total line of 9.0 aligns with the historical tendency for higher-scoring affairs in this particular matchup, especially considering both starting pitchers have demonstrated periods of vulnerability and the Nationals' overall team pitching metrics are less robust.