PEORIA, Ariz. -- Three-fifths of the Padres’ projected rotation faced hitters in a live batting-practice session at Padres camp on Sunday. Chris Paddack, Dinelson Lamet and Joey Lucchesi all made life difficult for a handful of position players who had reported to camp early.

The highlight of Sunday's session may have been Paddack's curveball, which he emphasized heavily in his bullpen session beforehand. Paddack then mixed it in regularly against hitters -- without anything more than a foul ball against it.

Paddack boasts a dominant fastball-changeup mix, but he spent most of his rookie season trying to hone his third pitch. Early in camp, the curveball is clearly a focus of Paddack's. He threw five or six impressive curves during Sunday's live BP, including two after pitching coach Larry Rothschild had reset the count to 0-0. (That speaks volumes to how much progress Paddack hopes to make with the pitch.)

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"I got a new grip, been working on a few things," Paddack said earlier this week of his curve. "The confidence, man, especially toward the end of the year last year, working on it all offseason -- it's the third pitch."

Paddack's curveball evolved steadily during the 2019 season. It started as a slow looping pitch, then he made it bite more sharply, and by the end of the season, he had added a few ticks of velocity. Here's a breakdown of three curveballs apiece from Paddack's first start, his 13th start and his 26th and final start:

We probably won’t know how much progress Paddack has made with his curveball until he uses it in games later this month. But he’s clearly pleased with the strides he’s made -- though he added a caveat.

"I'm never going to be satisfied or settled with where it's at," he said. "There's always room for improvement."

Richards facing no restrictions
Barring further injury, Garrett Richards is unlikely to be restricted in his workload in 2020. The veteran right-hander returned from Tommy John surgery late last season and went through his normal offseason progression this winter.

The Padres signed Richards to a two-year $15.5 million contract in December 2018 -- with an eye squarely on ‘20. It sounds as though they expect to use him as they would any other starting pitcher, and Richards has significant performance bonuses for each start he makes over 20.

Manager Jayce Tingler clarified that, of course, the Padres will monitor Richards closely. If there are any signs of trouble, they'll adjust their plans. But Richards has built past 200 innings in the past, and he's clearly capable of handling a big league workload.

"There's a responsibility you have any time a guy is coming off injury and certainly Tommy John," Tingler said. "I don't want to sit here and say we're going to baby anything, because that's not real, that's not true. He's going to come to dictate it by his health and by his work."

Cronenworth set for minimal mound work
Offseason addition Jake Cronenworth is being built up primarily as an infielder this spring, though Tingler said the Padres are also preparing for him to handle "one inning a week" on the mound.

A two-way player, Cronenworth arrived in November as part of the Tommy Pham trade. He batted .334/.429/.520 in Triple-A last season, and he even got on the mound for seven innings in which he didn't allow an earned run.

That unique skill set could give Cronenworth a leg up for one of the final places on the Padres’ roster. He's among a deep group of infielders vying for, at most, two available spots on the 26-man roster. (Cronenworth, of course, is the only one of those infielders with a 95-mph fastball and a plus curveball.)