The Washington Nationals are struggling to get the hang of the new ABS challenge system

WASHINGTON, DC - APRIL 03: A general view of the Washington Nationals ABS challenge on scoreboard during the eighth inning of the game against the Los Angeles Dodgers at Nationals Park on April 3, 2026 in Washington, DC. (Photo by Scott Taetsch/Getty Images) | Getty Images

This year has seen the introduction of the ABS challenge system to Major League Baseball, which is a game changer. It not only helps with accuracy, but it also provides a new strategic layer to the sport. So far, the Nationals have not picked up this new system quickly. In fact, they are the worst challenging team in the league.

Right now, the Nationals have won the fewest number of challenges at just 8, and also have the lowest percentage. The Nats have only won 32% of their challenges, which is the worst in the league by 9%. It is a jarring number, and one the Nats new coaching staff and front office will want to fix.

The Nats new analytically minded brain trust is going to want to find whatever edge they can. So far, the Nats have been unable to exploit ABS, which is a new way to find an edge. Right now, teams are just getting a handle on the ABS system, and how to use it.

Teams like the Twins are being very aggressive. They have made 58 challenges, more than double the Nats 25. Minnesota has also won them at a 59% clip. It is still an open question as to what the best ABS strategy is. Should teams be hyper-aggressive like the Twins, or more conservative?

The Nats have not made a high volume of challenges, but it does not feel like they are using them strategically either. They are just 5/16 on challenges before the 7th inning. That is an important metric because it shows the Nats are blowing challenges in lower leverage spots.

If you lose a challenge on a 3-2 pitch with runners on in the 8th inning, that is not a big problem. On a borderline pitch in that moment of the game, it is worth making sure if the umpire was right. If you challenge in lower leverage spots early in the game, you better be right. So far, the Nationals have not been right in those spots most of the time.

Despite being last in challenges won and percentage, the Nats are not at the very bottom when it comes to run value lost by challenges. They are 27th in that metric, behind the Angels, Guardians and Rangers. Even though the Nats are terrible at challenges, they are managing to be awful in a way that is not totally backbreaking. That is good I suppose.

However, the Nats are going to need to get better at this before too long. Both the hitters and catchers have been bad at this, it is not just one. Nats hitters are 29th in challenge win percentage and the catchers are dead last. It has been a problem for this team across the board, and one they need to fix before it is too late.

One moment that I think set the tone for the Nats challenge woes came in their series against the Phillies. The Nats ran out of challenges in the third inning that night, and since then, I feel like they have been caught in between. They seem to be in their own head and it leads to them not knowing when to challenge.

The next couple games after that Philly challenge disaster, they just weren’t challenging much at all. That led to missed opportunities in higher leverage spots where they could have challenged obvious missed calls. Right now, they just seem to be caught in between.

A couple of the main culprits for this are Nasim Nunez and Keibert Ruiz. Nunez has had some really baffling challenges on obvious strikes. Lately, it seems like he has had his challenge privileges revoked. Ruiz is also struggling with ABS. He is 1 for 5 on challenges, which is the worst mark by any catcher in the league.

Ruiz has improved a lot on the other aspects of his defensive game, but he is struggling to pick up this new wrinkle. Having a catcher who is bad at challenges puts you in a tough spot. You cannot just revoke their challenge privileges like a hitter because there are challenge opportunities for a catcher in every game. The best solution is just to coach up Ruiz and hope he gets better.

As for the Nats other catcher, Drew Millas is a bit better at challenging, but he is not elite. He is more aggressive than Ruiz, making 9 challenges so far. Millas is 4 for 9 so far, which is not terrible, but below the 60% average that fielders have.

So far, the Nats ABS struggles are not costing them games, but it will if this continues. I trust the coaching staff and know they are working very hard to try and fix this. Right now, it just feels like ABS is a mental block for Nats hitters. I also just think they are getting a bit unlucky. James Wood has had a couple challenge losses on pitchers that just nick the zone by a millimeter.

This is something we will be following throughout the season. I do not think the Nats will be this bad the whole way, but there is only one way to find out. ABS has provided a fascinating new wrinkle to the sport and I enjoy it. The accuracy improvement is great, but I also like the strategic aspect. Hopefully the Nats can get a hang of the ABS system and improve their strategies.