CHICAGO -- Tyler Chatwood jumped on the mound, slapped his glove and quickly glanced to the Cubs' dugout in the seventh inning on Saturday night. He had just yanked a cutter to the dirt, issuing a walk to Gregory Polanco that loaded the bases with two outs.

"I wanted that last one," Chatwood said.

Up to that point in the Cubs' 4-3 victory over the Pirates, Chatwood had been "totally in command," in the words of manager David Ross. The righty matched a career high with 11 strikeouts, set a career best with 20 swinging strikes and got the National League Central-leading North Siders into the seventh.

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Chatwood wanted that cutter to be enticing enough for Polanco to offer a feeble swing -- a theme throughout the evening. Instead, Jeremy Jeffress entered and escaped the jam and Chicago's embattled bullpen held on for dear life in a nail-biting ninth, pushing Chatwood into the win column.

While that last cutter was a misfire, it was that pitch that helped baffle Pittsburgh's bats throughout Chatwood's 6 2/3 shutout innings. It is an offering the righty tweaked last year and kept honing over the offseason and into Spring Training, and during the shutdown period and Summer Camp.

"That was a big emphasis in what I tried to work on in the off time," Chatwood said. "And I'm able to execute it right now."

What did Chatwood change?
In the middle of the summer last season, when Chatwood was relegated to a swing-man role on Chicago's staff, he knew he needed to make an adjustment with his cutter. The lack of effectiveness was helping lefty batters feast on his offerings.

"I was just fighting my cutter the whole year," Chatwood said. "It was too hard and I was getting around it to try to manipulate it. So I just went back to a grip I used to throw."

Without going into extreme detail, Chatwood said he reverted back to a grip similar to how he threw a slider in the past. The goal was to get more depth (combination of horizontal and vertical break) to better attack lefties, who hit at a .306 clip against him in '19 overall.

Chatwood only threw the cutter 10.2 percent of the time in '19. In that small sample, he held batters to an 0-for-15 showing with 11 strikeouts with the pitch from July 1 through the end of last season. The righty threw the pitch 31 percent of the time on Sunday and 24 percent in Saturday's outing.

"I got good feedback instantly," Chatwood said. "So I continued to work on it to make it go sideways and have depth."

What has the result been?
The improvement with the cutter has given Chatwood a pitch he can trust in a variety of ways to both left-handed and right-handed batters.

"It's just consistent," Chatwood said. "I feel like I can run it in at a lefty's hands, or try to have depth and down and away to a righty, or back foot to a lefty. I feel like I'm able to manipulate it two ways right now and the velocity stays on it, which I think is a big part."

Of their 20 swings and misses on Saturday, the Pirates whiffed seven times against the cutter, which checked in at 90.5 mph on average, per Statcast. He can pair that with a hard sinker that tails in the opposite direction. Add in the four-seamer, curve and changeup, and suddenly the once walk-prone Chatwood looks like a tough assignment.

"We faced him a lot when he was in Colorado. And it was hard," said shortstop Javier Báez, who belted one of three homers for the Cubs on Saturday night. "When he was throwing 98 and with that movement, it was tough to pick a side of the plate."

Pittsburgh managed to put just one of the 23 cutters thrown by Chatwood into play. Overall, the right-hander scattered three hits and walked two, but he sidestepped any harm with an assist from Jeffress.

Two starts into the season, Chatwood now has given up just one run with 19 strikeouts in 12 2/3 innings.

"Tyler's in a really good place right now," Ross said. "Great performance by him. We've come to expect that out of Tyler -- the way he showed up in Spring Training this year. And then, like I've said a number of times, he can wow you with a lot of stuff."