Hiroshima’s Atsushi Endo took the mound in the fifth inning on April 10, holding the Yakult Swallows scoreless in a relief effort that snapped the Carp’s losing streak. The 27-year-old hurler has now extended his season-opening scoreless streak to eight appearances, already surpassing his total from last season. Over 9 1/3 innings pitched, he has allowed just four hits, one walk, and struck out nine, maintaining a pristine 0.00 ERA.
What stands out is the marked improvement in his fastball quality. Across NPB this season, fastballs account for 41% of pitches thrown, but Endo relies on his heater a whopping 57% of the time. Despite this heavy usage, opposing hitters are batting just .111 against his fastball, with zero extra-base hits allowed. So why can’t batters square up his fastball? One clear factor is the “VAA” (Vertical Approach Angle), a metric increasingly valued in MLB.
VAA measures the vertical entry angle of the ball as it crosses home plate. Pitches thrown from the mound typically register a negative value (ranging from -4 to -7). Research suggests that flatter VAA values (closer to zero) tend to generate more swings and misses. While old-school baseball wisdom praised “angled fastballs,” the game’s evolution has shifted what hurlers aim for.
Carp analyst Ichioka commented, “We noticed batters would swing at pitches they shouldn’t, or be late on them. As we dug deeper, we realized that a shallow VAA angle was likely one of the reasons.” The metric has gained attention in Japanese baseball as well. Yakult’s closer Kihada, the league leader in saves in his first NPB season, along with Seibu’s Taira, are among those posting shallow VAA numbers. Endo has matched their elite readings.
Interestingly, Endo wasn’t deliberately chasing a better VAA. The breakthrough came two years ago when he was desperate to overhaul his mechanics after struggling to secure a regular first-team spot. In 2024, his fastball velocity sometimes dipped below 140 km/h. Determined not to let his career stall, he underwent motion analysis that offseason and decided to lower his arm slot. Through trial and error during the 2025 spring camp, he hit 151 km/h by March—a jump of over 10 km/h from a year earlier, setting a new personal best.
His precision has sharpened with each outing. In his third appearance of the season on April 29 against the Giants, he clocked 150 km/h, the fastest of his first-team career. The velocity gains were no fluke, and his fastball’s hop, spin rate, and approach angle have all improved.
Despite the advanced metrics, Endo insists he doesn’t visualize a flat fastball. Instead, he thinks of the old-school “angled” heater. “I’m not aiming high. I imagine throwing downhill and driving the ball into the bottom of the strike zone. If it ends up riding up and gets a swing-and-miss, that’s fine too,” he said.
His delivery resembles a drumstick whipping around a central axis, with his arm snapping like a baton. Rather than releasing the ball closer to the hitter, he focuses on the torque generated as he rotates his body. “It feels right, like my arm is clicking into place perfectly.” He never considered VAA or intentionally optimized it.
Analyst Ichioka agrees: “I don’t think he should make VAA his primary strength. It’s better that the angle naturally makes it harder for hitters to pick up the pitch.” Endo didn’t chase the new metric; the metric caught up to him. With naturally flexible elbows and relentless effort to reinvent himself as a pitcher, he stumbled upon a form that produced VAA as a valuable byproduct. —Maehara Jun
