Washington Nationals vs St. Louis Cardinals Picks and Prediction for Friday September 18 2026

The Washington Nationals visit the St. Louis Cardinals at Busch Stadium in St. Louis, Missouri, on Friday, September 18, 2026. First pitch is scheduled for 8:15 PM ET with coverage on MLB.TV. Washington enters at 71-82 overall and 34-41 on the road, while St. Louis is 75-78 overall and 37-41 at home. The Nationals have won four of their last five despite losing their most recent game, while the Cardinals have dropped two straight and three of their last five. St. Louis leads the season series 2-1 after the teams played three games in Washington in April. At the time of this writing the odds were not released. Be sure to check out our free MLB picks for more MLB predictions throughout the season.

Starting Pitchers

Washington is scheduled to start Cade Cavalli, who enters at 12-5 with a 3.12 ERA and 1.17 WHIP through 164.2 innings. He has allowed 144 hits and 18 home runs while striking out 194 and walking 48. St. Louis counters with Kyle Leahy, who is 10-4 with a 3.33 ERA and 1.31 WHIP across 135 innings. He has surrendered 139 hits and 14 home runs while recording 128 strikeouts against 38 walks. Both starters have delivered productive seasons, but the statistical advantage belongs to Washington. Cavalli owns the lower ERA and WHIP while producing 66 more strikeouts. Leahy has been solid in his own right, although his 1.31 WHIP suggests Washington could have more opportunities to put runners on base.

Washington Brings the Stronger Offensive Profile

Washington comes into the series at 71-82 overall and has been playing some of its better baseball recently. The Nationals are 4-1 over their last five games, with their only loss coming 3-0 against Philadelphia on Wednesday. Before that defeat, Washington had won four consecutive games, beating Philadelphia 6-3 after sweeping three games against the Angels by scores of 6-5, 6-5 in 10 innings and 4-3. The Nationals have been competitive in close games during this stretch, with three of those five contests decided by one run.

The Nationals own a .247 team batting average with 1,289 hits, 778 runs and 200 home runs. Washington has also produced a .323 on-base percentage and .426 slugging percentage. Its pitching numbers have not been nearly as strong, with a 4.71 ERA and 1.39 WHIP while opponents are batting .253. Washington has recorded 1,197 strikeouts against 572 walks and enters Friday with a 40-48 record in night games.

The biggest reason to consider Washington in this matchup is the combination of its offense and favorable starting-pitching comparison. The Nationals have scored 85 more runs than St. Louis and hold a 42-home-run advantage. Their .426 slugging percentage is also 44 points higher than the Cardinals' .382 mark. Washington's season-long pitching numbers create some concern, but the Nationals won't necessarily need their entire staff to carry the matchup if their starter can continue producing at his 3.12 ERA level.

St. Louis Looks to Reverse a Two-Game Slide

St. Louis enters at 75-78 overall and has struggled to establish a meaningful home-field advantage, going 37-41 at Busch Stadium. The Cardinals are 2-3 over their last five and have lost consecutive games. They fell 6-5 in 10 innings against San Francisco on Wednesday after a 10-3 loss the previous night. St. Louis did win two of the previous three, defeating San Francisco 2-1 and the White Sox 3-1, with a 6-5 loss separating those victories.

The Cardinals are batting .242 with 1,250 hits, 693 runs and 158 home runs. They have a .316 on-base percentage and .382 slugging percentage. St. Louis has been stronger on the pitching side, posting a 4.28 team ERA and 1.36 WHIP with opponents batting .254. The Cardinals have recorded 1,216 strikeouts against 532 walks. They have also been considerably better than Washington in night games, producing a 48-45 record.

St. Louis has a modest season-long pitching advantage, with its 4.28 ERA sitting 0.43 runs below Washington's 4.71 mark. The problem Friday is that the starting matchup does not necessarily reflect that team-level edge. Washington brings the lower starter ERA and WHIP into the opener, while its offense has also been substantially more productive over the course of the season. St. Louis did win two of three in the first series between these teams, but Washington scored 16 runs across those games compared with 19 for the Cardinals, so the earlier meetings were more competitive offensively than the 2-1 series margin might suggest.

Washington Nationals vs St. Louis Cardinals Picks and Prediction

Pick: Washington Nationals Moneyline

Washington is the side despite entering with four fewer overall victories. The Nationals have the better recent form at 4-1 over their last five compared with St. Louis at 2-3, and they also possess the stronger offensive numbers. Washington leads St. Louis in batting average, runs, hits, home runs, OBP and slugging percentage. The starting-pitching matchup adds another reason to lean toward the visitor, with Washington's starter carrying a 3.12 ERA, 1.17 WHIP and 194 strikeouts compared with St. Louis at 3.33, 1.31 and 128. With no confirmed price available, Washington is the preferred moneyline side if the eventual market remains reasonable.

Pick: Under 9 or Higher

The Under becomes attractive at 9 or higher because both scheduled starters enter with ERAs in the low threes. Washington's starter has a 3.12 ERA and 1.17 WHIP across 164.2 innings, while St. Louis counters with a 3.33 ERA over 135 innings. Recent results also provide some support: four of Washington's last five games finished with nine or fewer combined runs, including a 3-0 result Wednesday, while three of St. Louis' last five stayed at seven runs or fewer. Washington possesses the offensive numbers to make this dangerous, but a total of nine would provide enough room to back the stronger starting-pitching component of the matchup.

Final Picks: Washington Nationals Moneyline and Under 9 or Higher

This preview was completed on Thursday. Starting pitchers, betting lines and other game information are subject to change before the game begins.