OAKLAND -- Cole Ragans reached 99 mph a couple times before the fifth inning Wednesday afternoon, getting as high as 99.6 mph in the fourth against A’s outfielder Aledmys Díaz.

That’s pretty close to 100 mph, but not quite triple digits. In the dugout between innings, assistant pitching coach Zach Bove joked with Ragans about not hitting that elusive number.

So when Ragans clocked 101 mph on a ball to Shea Langeliers in the fifth inning of the Royals’ 4-0 win over the A’s at Oakland Coliseum for the fastest pitch of his career, of course Ragans checked the scoreboard for the velocity. And then he immediately looked over to Bove in the dugout.

“You see that?” Ragans seemed to say with his eyes and a chuckle.

“Oh yeah, I velo-checked that one,” Ragans said. “I let it go and was like, ‘All right, that’s got to be pretty hard.’ … I gave [Bove] a little look.”

Ragans dominated again with his velocity and mix of pitches to lead the Royals in the series finale. Backed by timely hitting from the offense that included Dairon Blanco’s first career homer and Bobby Witt Jr.’s 26th homer of the season, Ragans threw six scoreless innings with just two hits allowed. He didn’t walk a batter and struck out 11, matching his career high set against the Red Sox on Aug. 7. 

The pitch to Díaz in the fourth was the fastest of Ragans’ day until he threw 99.8 mph to Jordan Diaz in the fifth, tying his career high, before topping that against Langeliers.

In fact, 12 of the 20 fastest pitches in Ragans’ career came against Oakland. He averaged 98 mph with his fastball, a 1.8 mph jump from his season average. The A’s had no answer for it; they whiffed nine times on 14 swings against his heater (64%).

Ragans kept them off balance with his changeup, which registered a 41% whiff rate, and kept them honest with his cutter, slider and curveball.

"That was probably one of the best performances we’ve seen all season on the mound,” A’s manager Mark Kotsay said. “We’ve seen Ragans before, and the velo has definitely spiked. He was 98-100 today. The changeup was electric. I don’t think we got a good swing off it. And the angle of the slider.

“You see why that trade was made. They picked up a really good arm.”

The Royals had high hopes for Ragans when they acquired him from the Rangers for Aroldis Chapman at the end of June. And the 25-year-old lefty has been everything and more. In six starts with Kansas City, he has a 2.08 ERA. He’s thrown 34 2/3 innings and struck out 47 while walking only 10.

Ragans’ slider has also been impressive, and he threw that pitch harder Wednesday, too.

His velocity jump has been another surprising development, especially given that he’s able to sustain it throughout his outings. On his 99th and final pitch of the day, Ragans threw a 99.5 mph fastball that Zack Gelof swung through for strike three.

“What sticks out to me is that it’s fairly effortless when he does it,” Royals manager Matt Quatraro said. “All of his pitches are between 96-100 [mph] with the fastball, and you can’t tell a difference on which one will be which. It’s a credit to his delivery, the efficiency of it, his release, how his arm works and his conditioning.”

The velo increase started back when Ragans was with the Rangers, after an offseason spent with Tread Athletics. The program focused on his mechanics and mobility to help his body move better down the mound. He used weighted balls for the first time and got stronger. The goal wasn’t to throw harder; he simply wanted to maintain velocity throughout the season.

Instead, Ragans jumped up 4-5 mph. After averaging 92.1 mph on his four-seamer last year -- which ranked in the 19th percentile in MLB -- he is now sitting 96-97 mph and, as seen against the A’s, can hit 100 mph.

“It’s the same effort that it was when I was throwing 92,” Ragans said. "It’s just coming out hotter.”

When that velocity and tempo is paired with Ragans’ mix of pitches and command that he’s shown this season, hitters don’t often have answers. He threw 99 pitches (61 strikes) and was in the zone with more than half of the pitches he threw, including a 61% zone percentage with his fastball.

“He goes out there with a mentality that every pitcher should have,” Witt said. “Coming at you, attacking you. … Attacking the zone and checking out the scoreboard seeing 100 up there is always pretty cool to see.”