"He walked up to me and said, 'I can see a difference in just you playing catch' at the 75 feet or what it was at the time," Johnson said. "That was huge. I've felt good but then to have someone else say I can see a difference, can see the extension ... that was nice."
Johnson, who agreed to a one-year deal worth $8 million in November, is coming off a miserable year with the Blue Jays and surgery after the season to remove loose bodies in his right elbow, which had a profound impact on his struggles in 2013.
Johnson was 2-8 with a 6.20 ERA in 16 starts for the Blue Jays, a season that was interrupted by two stints on the disabled list. His last appearance came on August 6.
"Spring Training [in 2013], [the elbow] felt good, but there was something in there that wasn't bothering me yet," Johnson said. "We got to April and it started creeping in. You could tell that something wasn't quite there. I couldn't get to that extension."
Johnson said his elbow has felt great since his October surgery and that he's already been able to throw three bullpen sessions. He'll likely have two more before pitchers and catchers report to Arizona for the start of Spring Training on Feb. 13.
The Padres will allow Johnson to come along slowly in Spring Training. That's the case with a handful of other players coming off surgery -- including outfielders Cameron Maybin and Carlos Quentin. The goal, manager Bud Black said last week, is to keep players healthy through Spring Training and have them set for the start of the regular season on March 30.
"I talked to Bud and he was saying you might not go [pitch] every other day and we're going to play it by ear and see how you're feeling," Johnson said.
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.