Holland series 2026 Preview: Curaçao Neptunus and Amsterdam Pirates Set for Championship Showdown

The two best teams in Dutch baseball will decide the 2026 national championship when Curaçao Neptunus and Amsterdam Pirates open the Holland Series on Saturday, September 5 at the Neptunus Familiestadion in Rotterdam.

Game 1 of the best-of-seven championship series is scheduled for 14:00 local time, with the first team to four victories being crowned Dutch champion. Neptunus enters the final as the defending champion and regular-season winner, while Amsterdam returns to the Holland Series looking for its first championship since its dramatic title run in 2023.

On paper, Rotterdam has been the stronger team over the full season. On the field against Amsterdam, however, the difference has been almost nonexistent.

Neptunus and Amsterdam were clearly the top two teams in 2026

Curaçao Neptunus dominated the regular season with a 33-3 record (.917), finishing three games ahead of Amsterdam Pirates at 30-6 (.833). Neptunus scored 262 runs while allowing only 73 during the regular season, giving Rotterdam a remarkable +189 run differential. Amsterdam scored 233 and conceded 104, good for a +129 differential.

The gap between the top two and the rest of the Hoofdklasse was substantial. Third-placed Oosterhout Twins finished 19-17, while Kinheim went 18-17 with one tie. In other words, the Holland Series brings together the two teams that separated themselves from the field throughout 2026.

Neptunus is also chasing another piece of history. Rotterdam defeated HCAW four games to two in the 2025 Holland Series to capture its 21st Dutch national championship, after also winning the title in 2024. A victory this year would therefore complete a three-peat and give the club championship No. 22.

Amsterdam knows what it takes to stop Rotterdam. The Pirates’ most recent championship came in 2023, when they defeated Neptunus 4-3 in a memorable seven-game Holland Series that ended with a 9-8 Amsterdam victory in the deciding game.

2026 head-to-head: a perfect 3-3 split

Perhaps the biggest reason not to read too much into the regular-season standings is the season series between the two finalists.

Neptunus and Amsterdam met six times during the regular season — and split those games 3-3.

Their first series started with an emphatic 11-1 Neptunus victory on May 28, but Amsterdam responded two days later by sweeping a doubleheader, 3-0 and 6-4. The first of those victories ended what had been a 16-game unbeaten run by Neptunus.

When they met again at the end of July, the balance shifted. Neptunus won 6-2 in Amsterdam on July 30 and followed it with a 3-0 victory in Rotterdam on August 1. Amsterdam then took the second game of that August 1 doubleheader, 8-7, handing Neptunus its first home defeat of the season and ending Rotterdam’s 17-game home winning streak.

That 3-3 split makes the championship matchup considerably more difficult to predict than the overall records suggest.

Expected Game 1 matchup: Lars Huijer vs. Koen Postelmans

The starting pitchers for Saturday have not yet been officially confirmed, but the expected Game 1 matchup is currently Lars Huijer for Amsterdam Pirates against Koen Postelmans for Curaçao Neptunus.

If confirmed, it would immediately give the Holland Series a high-level pitching duel.

Postelmans has been among the most effective pitchers in the Hoofdklasse this season. The current 2026 league leaderboard lists the Neptunus right-hander with a 1.08 ERA, second only to teammate Juancarlos Sulbarán’s 1.06 among the listed ERA leaders. Huijer follows directly behind them at 1.66 for Amsterdam.

Postelmans carried an 8-0 record late into the regular season. His performances included four innings in a combined two-hitter against Oosterhout Twins on June 6 and another strong outing as part of a combined two-hitter against HCAW one week later. He reached 8-0 with Neptunus’ 9-2 victory over Kinheim on July 25.

Huijer went 8-2 during the regular-season schedule and delivered one of the best pitching performances of the entire Hoofdklasse season on July 18, throwing a no-hitter against Hoofddorp Pioniers in an 11-0 Amsterdam victory. He followed that with seven innings in a combined two-hitter against UVV five days later.

Huijer also brings substantial Holland Series experience against this particular opponent. Pitching for HCAW in the 2025 final, he worked all ten innings of Game 1 as HCAW defeated Neptunus 3-1. He now gets the opportunity to challenge Rotterdam’s lineup again, this time wearing an Amsterdam uniform.

Expected Game 1 starters, pending confirmation: Amsterdam Pirates — RHP Lars Huijer; Curaçao Neptunus — RHP Koen Postelmans.

Neptunus lineup has been relentless

Rotterdam’s greatest strength is that there is no obvious section of the batting order for an opposing pitcher to relax against.

The 2026 Hoofdklasse leaderboard currently has Stijn van der Meer (.462), Christian Diaz (.438) and Darryl Collins (.412) occupying the first three positions in batting average. Diaz also leads the listed league statistics with 63 hits and 44 RBI, while Collins has contributed 56 hits and 36 RBI. Dwayne Kemp provides another dimension with five home runs and 18 stolen bases.

That depth was evident when Neptunus clinched its Holland Series place against Kinheim.

After surprisingly losing the opening game of the semifinal 7-2, Rotterdam responded with consecutive victories of 2-1, 5-0 and 9-1 to take the best-of-five series 3-1. In the deciding game, Neptunus erupted for 17 hits. Sem Kuijper went 4-for-4, Collins finished 3-for-4, Drew Janssen collected two hits and Kemp homered. Shairon Martis worked seven innings before Chris Stuart and Ryan Huntington finished the game.

It was precisely the type of all-around performance that makes Neptunus so difficult to beat four times in a series.

Amsterdam has the speed and power to punish mistakes

Amsterdam’s offense has a different profile but is hardly less dangerous.

Tommy van de Sanden, Jeandro Tromp and Delano Selassa have all been among the league’s leading hitters in 2026. The current leaderboard lists Van de Sanden at .400, Tromp at .398 and Selassa at .377, while Tromp and Van de Sanden rank first and second in OPS at 1.148 and 1.126 respectively.

Amsterdam also has the ability to manufacture pressure on the bases. The Pirates’ team statistics list 83 stolen bases, compared with 62 for Neptunus, while Amsterdam also holds an 18-15 advantage in home runs. Selassa alone has 21 stolen bases on the current league leaderboard, with Alex Madera adding 15.

That combination of patience, speed and extra-base power could be especially important against a Neptunus pitching staff that rarely gives opponents extended scoring opportunities.

Amsterdam enters the Holland Series after overcoming Oosterhout Twins in an unusual semifinal. The Pirates won Game 1 by 8-1 and Game 3 by 9-4, while Game 2 became the subject of a successful Amsterdam protest involving the application of the hidden-ball rule. The game had to be resumed from the seventh inning, after which Amsterdam ultimately secured its place in the final.

Neptunus pitching depth could decide a seven-game series

The biggest statistical advantage for Rotterdam may come on the mound.

Neptunus’ 2026 team pitching figures list a 1.90 ERA and 1.01 WHIP, compared with Amsterdam’s 2.83 ERA and 1.15 WHIP. Rotterdam can move beyond Postelmans to a deep group that includes Juancarlos Sulbarán, Shairon Martis, Tom de Blok, Kevin Kelly, Chris Stuart, Ryan Huntington and others.

That depth becomes particularly valuable in a best-of-seven series with games scheduled across three consecutive weekends.

Amsterdam is certainly capable of matching elite starting pitching — Huijer is the obvious example — but Neptunus has more ways to construct nine innings when a starter leaves early. Keeping the game close enough to avoid handing Rotterdam’s bullpen a lead will therefore be one of the central challenges for the Pirates.

2026 Holland Series schedule

Games 5-7 will be played only if necessary.

Holland Series outlook: very little separates these rivals

Neptunus deserves to enter the 2026 Holland Series with a slight advantage based on its complete body of work. A 33-3 regular season, outstanding run prevention, a deep pitching staff and a lineup containing several of the league’s best hitters make Rotterdam an exceptionally difficult opponent in a seven-game format.

Amsterdam, however, has already demonstrated that it can beat Neptunus. The clubs finished 3-3 against each other during the regular season, and the Pirates won two of three during their first meeting of the year. They also possess an experienced potential Game 1 starter in Huijer and an offense capable of changing a game through both power and aggressive baserunning.

If the expected Lars Huijer-Koen Postelmans matchup is confirmed, Saturday’s opener should provide an immediate indication of how tight this Holland Series could become. With two elite offenses, two deep pitching staffs and the Netherlands’ two most successful teams of the 2026 season facing each other, there is little margin for error.

For Amsterdam Pirates, four wins would bring the championship back to the capital for the first time since that unforgettable seven-game triumph over Neptunus in 2023.

The 2026 Holland Series begins Saturday in Rotterdam.