Certainly a different pitcher than the one the Padres had seen of late.
"He was outstanding," said Padres manager Andy Green. "We talked in between starts and it just felt like he wasn't finishing out front, there wasn't a ton of conviction in his last couple starts prior to today.
"And from the first pitch today, you could see him out in front, you could see him finishing aggressively."
Jackson faced the league's most potent offense and, with his adjusted finish, delivered seven shutout innings with 11 strikeouts -- the most of any Padre pitcher this season and the most he has tallied since May 17, 2014.
Jackson went to Green between starts and asked if anything looked different. The 32-year-old righty posted a 3.62 ERA through his first five starts with San Diego, but struggled in his most recent three, allowing 18 earned runs in 11 2/3 innings -- for a 13.89 ERA.
"You like to get different view points from different people," Jackson said. "About, not necessarily from the obvious: not throwing strikes. But just from appearance. How you look, the demeanor..."
Green told him he wasn't finishing like he used to. So Jackson made the adjustment.
"I mean, you don't have a choice. You adjust or you keep struggling," he said. "It's one of those things where you're not really worried about how difficult it is [to make that adjustment]. It's just a matter of how quick you can do it, and during a game, making adjustments from pitch to pitch."
Jackson said he was able to attack hitters more effectively Monday; be the aggressor and make Boston's hitters chase pitches after getting ahead, rather than work from behind like he had done in his previous three starts.
After throwing strikes just 56 percent of the time during those three games, Jackson threw 64 percent of his pitches for strikes Monday, while walking just one batter en route to his most impressive outing of the season.
"Today was one of those games," Jackson said. "It was definitely a positive, especially after the last few starts that I've had. That was just one of those things where, like I said before, you just have to keep working and keep grinding.
"And have belief that you can go out there and have a great game."