Lineup protection is real for the Royals and Carter Jensen’s data proves it

The idea of lineup protection is one that has threads throughout baseball history. The notion that a hitter sees better pitches when a dangerous batter follows him in the order is not new, although the debate is far from settled in the sabermetrics era. There is not much debate about whether the effect is real; rather, the question is how much the batters in the equation see different pitches.

One side of this idea for the Kansas City Royals has seen some quantifiable success in catcher Carter Jensen leading off. In fact, while the backstop is undoubtedly talented, he might not be riding a franchise-record hitting streak if not for batting leadoff.

One old baseball tactic could be fueling Carter Jensen’s June surge

According to Pitcher List’s analysis, Jensen’s pitch hittability on a rolling 400-pitch basis bottomed around 16.0% in mid-May, well below his season average and near the league’s 10th percentile. Then it climbed steadily to approximately 18.2% by June 25, crossing above the MLB average line and approaching the 75th percentile. That trajectory aligns with his move to the leadoff spot directly in front of shortstop Bobby Witt Jr.

There are multiple studies that prove a protected batter will see more strikes than an unprotected batter, but strikes can still be hard to hit. The Pitcher List pitch hittability chart captures the quality of pitches Jensen is seeing, which is a more nuanced metric. A pitch can be in the zone and still be unhittable (a well-located fastball on the hands, a back-door slider on the corner). Pitch hittability measures how attackable the pitch actually is. Jensen’s hittability climbing from the 10th percentile to near the 75th percentile is a larger effect than what the zone-rate studies capture.

Jensen started 2026 strong and seemed to be building upon his 2025 debut action, but cooled off immensely once the calendar turned to May. His 88 wRC+ and .222/.306/.383 line through May 27 were respectable for a rookie, but hardly the heights the Kansas City metro native showed fans in 2025 and early 2026.

But the next game he played in, May 30, marked the shift to him being Kansas City’s primary leadoff option. And while Witt has not batted directly behind Jensen in every game since, the effects are hard to ignore. Jensen has nearly doubled his season home run total in the past month, while posting a .287/.325/.509 line and 124 wRC+. It is a turnaround that does wonders for solidifying Jensen’s spot as a new member of Kansas City’s core.

This also coincides with Jensen getting more work behind the plate, thanks to team captain Salvador Perez’s slide and first baseman Vinnie Pasquantino’s injury. The extra opportunities have showcased that Jensen is an above-average framing catcher, while being one of the league’s most valuable catchers at limiting stolen bases, even if his blocking remains under scrutiny.

Overall, this lineup move has been overshadowed by the overall run-scoring gains for the Royals, but this is something Kansas City should stick with no matter the team results. This gives Jensen a better opportunity to showcase his talents and gives Witt someone on base in front of him, a luxury that Royals fans know is not reliable with this squad.