What Can We Take Away From Carter Jensen's Defense?

Initially seen as a backup going into the 2026 MLB season, Carter Jensen has ended up receiving most of the catching duties recently due to minor injury issues to Salvador Perez. While Perez's issues haven't required a stint on the IL, Jensen has actually surpassed Salvy in catcher innings this season, as seen in the fielding data table below.

It's been a bit of a mixed season for Jensen behind the plate defensively.

On one end, he only has one throwing error, which puts him at a fielding percentage of .994. He's also thrown out six baserunners this year, which is tied for the seventh-most in Major League Baseball, according to Fangraphs. 

That said, he's allowed four passed balls and eight wild pitches, a sign that his blocking hasn't been all that effective this year. Not only does he have three more wild pitches allowed than Perez, but he has also allowed four more passed balls.

Thus, some Royals fans are wondering if Jensen can be a catcher long term, or if he'll play himself out of the position, much like former Royals catching prospect MJ Melendez, who eventually moved to the outfield. 

Let's take a look at what's gone well for Jensen defensively, what needs improvement, and what his long-term outlook is as the catcher of the future in Kansas City.

Framing and Throwing Have Been Solid

When it comes to evaluating a catcher, there are three areas to focus on: blocking, framing, and throwing. I talked about these in separate offseason posts and how the Royals catchers performed in these three areas in 2025.

So far, this is how Jensen has fared in those three categories, per Baseball Savant.

I will get to the Blocks Above Average numbers in a bit. On a positive note, he's done extremely well in terms of throwing runners out on the bases, as well as framing. He ranks in the 92nd percentile in CS (above average) and the 84th percentile in framing. He is two runs above average this year in both of those categories.

In terms of CS Above Average metrics, he's posting a caught-stealing rate of 33%, which is 18 percentage points higher than his estimated caught-stealing rate of 15%. Jensen has succeeded with throwing runners out due to his excellent poptime, which measures quickly, in seconds, a catcher can get the ball out of his glove and to the base on a stolen base or pickoff attempt.

Here's a look at Jense's throwing metrics from the past two seasons, via Savant.

According to Savant, Carter's CS Above Avg./Throw of 0.19 is the fourth-best mark of qualified MLB catchers, and his 81.9 MPH arm strength ranks 12th. Thus, in terms of pure throwing tools, Jensen has been every bit as good, maybe slightly better than Salvy, which certainly says something.

In addition to his throwing, Jensen has been strong when it comes to framing, something that the Royals catchers have done better under bench coach Paul Hoover (who primarily works with catchers). Overall, the Park Hill High School product is two framing runs above average, with a 48.9% shadow-strike percentage. Not only is that 8.5 percentage points better than his mark last year, but it is also the 10th-best mark in Major League Baseball, according to Savant. 

It's interesting to see not only Jensen's improvement overall when it comes to framing, but how his framing has improved in certain areas of the strike zone, especially since his rookie debut in 2025. 

Jensen rates above the league average in the following zones:

• Zone 12 (59.8% to 46.8%)
• Zone 13 (36.7% to 21.6%)
• Zone 17 (32% to 30.8%)
• Zone 18 (53.9% to 49.7%)
• Zone 19 (28.9% to 24.1%)

For those unfamiliar, here is a look at where those numbers are situated in relation to the strike zone.

Thus, it seems like Jensen has been effective at getting strikes in those lower edges of the strike zone, as well as the top middle and top right areas. Those are areas where Perez has struggled, according to Savant. Thus, Jensen has, at the very least, provided a nice change in framing profile that should make the Royals a little well-rounded when Perez returns to regular duty behind the plate.

Blocking Has Been a Struggle for Jensen

While the throwing and framing have been excellent from Jensen, it's been a different story on the blocking end.

Jensen ranks in the bottom first percentile in blocks above average with a -8 mark. His BAA mark is worse than that of Agustin Ramirez of the Marlins, who had a -6 mark and was recently optioned to Triple-A Jacksonville to work on his catching defense. 

When it comes to his metrics over the last two seasons, Jensen has struggled in the blocking area since debuting with the Royals in 2025. He had a -2 BAA mark in 219 opportunities, thus bringing his career total to -10 with this season's -8 BAA. 

Here's a look at his full breakdown in blocking metrics, via Baseball Savant.

It's interesting to see the kind of plays where Jensen has struggled. In addition to having a higher BAA/G this year (-0.41) compared to a season ago (-0.38), he has particularly struggled on easy and tough pitches. His BAA on easy and tough pitches is a combined -6. His BAA on medium pitches has been slightly better at -2, but that mark isn't good either. 

An interesting comparison is Melendez, who was poor as a blocker as well in 2022, when he played the most catcher at the MLB level. According to Savant, he posted a -26 BAA mark and a -0.35 BAA/G mark in 2,932 block opportunities. That lackluster blocking ability was a big reason why the Royals opted to move Melendez to the outfield full-time in 2023.

The main difference between Jensen and Melendez is that Jensen was a much better framer. In 2022, Melendez produced -16 catcher framing runs and had a 41.7% shadow strike rate. That's a far cry from Jensen's framing numbers this year. Thus, it made more sense to move Melendez to the outfield based on his framing and blocking struggles, while Jensen really only struggles in blocking. 

What Does the Future Look Like for Jensen Behind the Plate?

Jensen is getting all the opportunities to show he can be the Royals catcher long-term. While Salvy isn't a 100 percent, he's been showing his age this season. After another 0-for-3 performance, the Royals captain is hitting .191 with a .555 OPS, and the Statcast percentiles don't look encouraging either.

As for Jensen, he's been on a bit of a cold streak, as he's hitting only .111 with a .374 OPS in 31 plate appearances in May. However, he's been trending up this weekend in the series against the Tigers, and his Statcast percentiles have been much better than Perez's this season, especially in terms of bat speed and exit-velocity ability. 

What will be key for Jensen going forward and succeeding Perez as the full-time catcher will rest on his blocking and how that develops.

I know some have pointed out that pitchers have had a better ERA with Perez than Jensen, which some say points to his game-calling. However, catcher ERA is not a sticky metric and is often influenced more by pitcher quality than by a catcher's game-calling ability (this Reddit thread provides a good breakdown of the topic). 

In terms of blocking, I do believe part of that is due to form and just adjusting to being an MLB catcher. There are some blocks that seem more mental, resulting from losing concentration in key moments. We saw during the Tigers game on Friday that Jensen was unable to make an out because the ball popped out of his glove on a throw from Bobby Witt Jr. Below is a video example. 

I believe many of Jensen's passed balls and struggles with blocking stem from issues similar to those seen in the clip above. He can physically do it. It's just having the concentration and mental fortitude to do it night after night, which is easier said than done. 

That said, the only way for Jensen to get better at blocking is to get more experience and innings behind the plate. With Salvy out, that's happening. 

While that's causing some struggles now, it will help him blossom more as a player when he gets older. 

With his hitting, throwing, and framing ability, can Jensen be at least an average blocker in the next 2-3 years? If so, he could be an All-Star catcher sooner rather than later.