Vladimir Guerrero Jr. went 0‑for‑14 with a run scored on Saturday at Comerica Park, extending a month‑long funk that began when Casey Mize returned to Detroit’s rotation. The May slump pushed his average to .118, the lowest mark of the season, and his last extra‑base hit was a double on April 28.
The timing of Guerrero’s struggles could hardly be worse for the Toronto Blue Jays, who entered May competing for positioning in the American League East against the New York Yankees and Boston Red Sox. Guerrero, who signed a seven-year, $175 million extension in 2024, remains the heart of Toronto’s offense, supplying roughly 30% of the club’s total bases. His barrel rate fell from 10.2% in April to a meager 3.7% in May, while his hard‑hit rate slipped below league average. A video review showed Mize’s deceptive sink and tighter command forced Guerrero into unfamiliar contact zones, exposing swing‑mechanics concerns noted earlier in the year.
In May his BABIP sank to .212, hinting that bad luck compounded the quality of his contact. The front office has scheduled a mid‑week video session to fine‑tune his swing path, and GM Ross Atkins hinted that a modest launch‑angle tweak could rekindle his power surge. While his exit velocity still averages 93 mph, the decline in wRC+ to 78 underscores the urgency of the adjustments.
What triggered the sudden dip?
Casey Mize’s activation was the catalyst; the left‑hander’s improved command forced Guerrero into unfamiliar zones, exposing the lingering swing‑mechanics issue scouts flagged earlier. The former first overall pick in the 2018 MLB Draft, Mize missed the first two months of the season with a forearm strain but returned with renewed velocity and pinpoint location on his split-finger fastball—historically one of the most devastating pitches in the American League against right-handed hitters.
“Mize has always had that swing‑and‑miss ability, but what we’re seeing now is execution,” said one AL scout who requested anonymity. “He’s painting corners and getting that sink to tail away from righties at exactly the wrong height. It’s not just Guerrero—teams are noticing.”
With two outs in the fourth, Mize induced a foul tip and weak contact that left Guerrero shaking his head, a reaction captured by on‑field cameras. The moment encapsulated a troubling trend: Guerrero, who posted a career-high 42 home runs in 2025, has looked increasingly helpless against quality left-handed pitching this month.
Stat line highlights from the May slump
According to Sporting News, Guerrero’s last homer came on April 20, and he has not recorded an extra‑base hit since April 28. In the five games after Mize’s return, he logged one run and struck out 12 times. His wRC+ dropped to 78, far below his season‑long 115.
Additional data from MLB.com shows his OPS fell to .560 in May, and his left‑handed splits dipped to a .090 average, highlighting the left‑handed pitcher’s impact.
The statistical erosion extends beyond the Mize matchup. Guerrero’s contact rate on pitches in the zone dropped to 78.3%, down from 86.1% in April. His chase rate increased to 34.2%, suggesting pitchers are successfully baiting him outside the strike zone. Most concerning, his pull‑side power—historically his calling card—has evaporated, with only three pulled balls in play during the entire month.
Historical context and player backgrounds
Guerrero, the son of Hall of Famer Vladimir Guerrero Sr., entered the 2026 season as the Blue Jays’ unquestioned cornerstone. After a breakout 2024 campaign where he hit .315 with 38 homers and 102 RBIs, the Blue Jays locked him up with the franchise’s richest contract ever. The Dominican phenom has long been compared to his father, but his swing mechanics have always carried more loft than the elder Guerrero’s legendary flat path.
Mize, meanwhile, represents Detroit’s best hope for rotation stability after years of rebuilding. The Auburn product has dealt with injury setbacks throughout his career, including Tommy John surgery in 2022, but his stuff when healthy ranks among the best in the AL Central. His sinker now sits at 96-97 mph with exceptional vertical movement, while his splitter generates whiff rates above 40% when located properly.
Key developments
- Guerrero’s BABIP fell to .212 in May, suggesting bad luck compounded by poorer contact quality.
- Casey Mize posted a 2.45 ERA in his first two starts against Toronto, directly limiting Guerrero’s production.
- Toronto’s coaching staff announced a mid‑week video session focusing on swing‑path adjustments for Guerrero.
- The Blue Jays’ team OPS with runners in scoring position dropped 87 points in May, directly correlating with Guerrero’s decline.
- Guerrero’s hard-hit rate fell below 35% for the first time since his rookie season, per Statcast data.
Coaching strategies and what’s next for Toronto?
The slump threatens the Blue Jays’ run‑scoring engine as Guerrero accounts for roughly 30% of the team’s total bases. Toronto’s hitting coaches, led by manager John Schneider’s staff, have identified several adjustment points. The mid‑week video session will focus on replays from Guerrero’s successful April, when his swing plane was more level and his load sequence more consistent.
“We’re looking at the trigger point,” explained one Blue Jays assistant coach. “When Vlad is at his best, his hands stay back and he creates that natural lift. Right now, he’s getting beat to the ball because he’s rolling over early.”
If the trend continues, Toronto may lean on emerging talent like outfielder Alek Manoah’s younger brother, who hit .285 in the past week, to fill the offensive gap. However, the front office remains optimistic; GM Ross Atkins believes a small launch‑angle tweak could restore power, and analysts note his exit velocity still averages 93 mph. A quick correction could reignite production before the final stretch.
Historical precedent offers reason for cautious optimism. In 2023, Aaron Judge endured a similar May collapse after facing elite stuff from left-hander JP Sears, only to launch 18 home runs in June. The adjustment process for elite hitters often requires only slight mechanical tweaks rather than wholesale changes.
“Guerrero’s ceiling remains as high as anyone in baseball,” noted one opposing front office executive. “The tools are all still there—exit velocity, bat speed, barrel ability. This is a processing issue, not a physical decline. Get him seeing the ball again, and you’ll see the production return.”
The Blue Jays face a critical two-week stretch against AL East rivals beginning next Monday. How quickly Guerrero can rediscover his swing could determine whether Toronto stays in the division race or fades into a wild-card battle.
When did Vladimir Guerrero Jr. last hit a home run?
His most recent homer came on April 20, 2026, against the Detroit Tigers, before the month‑long slump began.
How did Guerrero’s OPS change in May?
Guerrero’s OPS dropped to .560 in May, a stark decline from his season‑long .845, reflecting the broader offensive dip.
What specific adjustments are being considered?
Coaches are evaluating a slight increase in launch angle and a more level swing path, both aimed at raising his barrel rate back above 5%.