Statcast of the Day: Windy Wrigley yields rare homers

Cubs' Bryant, Pirates' Cervelli both go deep on batted balls with hit probabilities of 6 percent

Statcast of the Day: Windy Wrigley yields rare homers

When the wind is blowing out, Wrigley Field is a hitter's paradise and a pitcher's nightmare.

That was the case for the Cubs and Pirates on Saturday afternoon, as the teams hit what Statcast™ reveals were two of the least likely home runs you will ever see in Pittsburgh's 8-7 win. On a day when the wind was blowing out to center field at 24 mph at game time, the clubs smacked six homers total -- only one of which was of the no-doubt variety.

"You [as a hitter] definitely have quite the advantage when you're playing in this ballpark and the wind's howling out like that," said the Pirates' Andrew McCutchen, whose three-run shot in the top of the seventh inning gave his team an 8-6 lead.

The first big fly of the day needed no help to reach the seats. Chicago's Kris Bryant, homerless in 2017, crushed a pitch from Tyler Glasnow with a 104.7-mph exit velocity and 33-degree launch angle. Statcast™'s hit probability metric shows that batted balls with that combination go for hits 80 percent of the time -- with almost all of those winding up over the fence. In this case, Bryant's blast rode the jet stream over the bleachers and caromed off the giant video board beyond, resulting a projected distance of 451 feet. That made it the fourth-longest homer of Bryant's career.

On another day or in another ballpark, that might have been it for balls clearing the fence. That was not the case on a blustery afternoon at the Friendly Confines.

The other five round-trippers all had hit probabilities below 50 percent. Josh Harrison's first homer of the season, a solo shot in the seventh with a 96.7-mph exit velocity and 27-degree launch angle, was calculated at 42 percent. McCutchen's (97.0 mph, 33 degrees), was calculated at 30 percent. And Starling Marte's solo job off Jake Arrieta in the sixth (96.2 mph, 39 degrees) carried into the left-field bleachers despite a meager 8-percent hit probability.

Marte's solo homer

Then there two others -- one by the Pirates' Francisco Cervelli in the second and Bryant's second of the day in the ninth -- that overcame even greater odds.

Cervelli got the Bucs on the board, connecting an up-and-in fastball from Arrieta with a 95.7-mph exit velocity and 41-degree launch angle. That combination gave it a hit probability of only 6 percent, and yet the ball flew into the center-field seats. At a projected 392 feet, it was the farthest homer of the Statcast™ Era that was hit at less than 98 mph and with at least a 40-degree launch angle.

"You just pray they don't get the ball in the air too many times," Arrieta said of his approach Saturday. "The Cervelli homer, I feel he was jammed a little bit and still got it out. Two fly balls that just left the yard. They were solo homers and if you're going to give them up, you prefer nobody on base. I don't think you see a day where the wind blows harder than it did today."

Batted balls hit with a 96-mph exit velocity and 41-degree launch angle have gone for hits only about 6 percent of the time.

Bryant's second homer, a solo shot, brought the Cubs within a run in the bottom of the ninth. It shared with his first a 33-degree launch angle, but this one was hit nearly 15 mph softer (89.9 mph). The result was, once again, a 6 percent hit probability.

Nonetheless, the fly ball kept drifting back and back until it dropped into the basket just beyond the left-center-field wall at a projected distance of 383 feet. In the Statcast™ Era, only one other batted ball hit at less than 90 mph has flown farther.

Home runs like these still count the same, but as Statcast™ shows, the pitchers would be justified in feeling they encountered a heaping dose of bad luck.

Andrew Simon is a research analyst for MLB.com. Follow him on Twitter @AndrewSimonMLB. This story was not subject to the approval of Major League Baseball or its clubs.