Jameson allowed five hits and one walk while striking out six over 3.2 relief innings to earn a hold in Monday's 7-5 win over Colorado.

EDGE Analysis

Starter Ryne Nelson put the Diamondbacks in an early 4-0 hole, but Arizona's bats and Jameson's multi-inning relief effort bailed him out. Jameson made his first appearance since being recalled from Triple-A Reno and figures to work as a multi-inning reliever, who can spot start if need be. He started three games for Arizona earlier this season but was optioned to the minors following a disastrous one-inning outing against the Padres. The right-hander had lost the ability to command his slider and became too predictable, leaning too heavily on his fastball, per Nick Piecoro of the Arizona Republic. He rediscovered the slider in the minors, and it was the pitch he used the most often Monday (28 times among 59 pitches).

Jameson will throw out of the bullpen for Arizona, Steve Gilbert of MLB.com reports. The right-hander was called up Saturday when the Diamondbacks sent Brandon Pfaadt to the minors.

EDGE Analysis

A rotation shakeup loomed as Zach Davies was activated from the injured list to start Saturday. That transaction coupled with the Pfaadt demotion signaled an easy one-to-one-swap of Davies and Pfaadt. However, things got murky during Saturday's game when manager Torey Lovullo brought starter Tommy Henry in as a reliever, which led to speculation about Jameson entering the rotation and Henry going to the bullpen. Lovullo cleared up matters following the game, noting that the left-handed Henry will remain in the rotation and pitch Wednesday -- he faced four batters and threw just 10 pitches. Jameson is expected to serve in a multi-inning relief role.

Jameson was recalled from Triple-A Reno on Saturday.

EDGE Analysis

Jameson made three starts and three relief appearances early in the season, winning two games and saving another, but he was optioned in late April despite recording a 3.71 ERA. His 16.0 percent walk rate was worryingly high, and while he cut that mark down to 8.9 percent across five Triple-A starts, he also posted a 5.79 ERA. His promotion Saturday comes in the same set of transactions as Brandon Pfaadt's demotion but also Zach Davies' return from the injured list, so Jameson may have to settle for a relief role for now.

Jameson was optioned to Triple-A Reno by the Diamondbacks on Monday.

EDGE Analysis

He's be the corresponding move for Tommy Henry, who will start Monday's game against the Royals. Jameson has labored in his last two starts, lasting just one inning in his most recent outing. He should join Reno's rotation to work on his efficiency. The rotation spot vacated by Jameson could potentially be filled by Brandon Pfaadt.

Jameson (2-1) allowed three runs on three hits and three walks in one inning Sunday, striking out one and taking a loss against the Padres.

EDGE Analysis

Jameson needed 43 pitches to get through a disastrous first inning and didn't even get the opportunity to go back out. The Padres batted around the lineup, and most of the damage came on Matt Carpenter's two-run double. Prior to Sunday's outing, Jameson had allowed just four runs through 16 innings this season. He saw his ERA jump from 2.25 to 3.71 alongside a 16:12 K:BB. Jameson's next outing is currently scheduled to be in Colorado.

Jameson did not factor into the decision Tuesday against the Cardinals, allowing two runs on four hits and four walks over 3.2 innings. He struck out three.

EDGE Analysis

Jameson continues to provide valuable innings on the mound for Arizona. The 25-year-old has acquired two impressive wins and a save on the season, posting a 2.25 ERA and 1.25 WHIP over 16 innings between the rotation and bullpen. While he did not factor into this decision, Jameson limited the Cardinals' batters to two runs on four hits before being relieved in the fourth inning. He figures to get another start in the upcoming series with San Diego while Zach Davies (oblique) remains sidelined.

Jameson may make multiple starts as a fill-in for Zach Davies, whose oblique strain is expected to take "several weeks" to heal, Nick Piecoro of The Arizona Republic reports.

EDGE Analysis

Arizona manager Torey Lovullo described Davies' injury as "more than a (Grade) 1," with a Grade 1 strain being the least severe. Jameson excelled in his first start as a replacement for Davies, shutting down the Brewers over four scoreless innings last Wednesday. His next expected start is Tuesday in St. Louis. Jameson pitched as a starter in spring training -- he eventually lost out on the No. 5 job to Ryne Nelson -- and should be able to build up higher pitch counts and get deeper into games.

Jameson did not factor into the decision Wednesday, tossing four scoreless innings on three hits and zero walks during a 7-3 win over Milwaukee. He struck out four.

EDGE Analysis

Jameson was filling in for Zach Davies, who was recently placed on the 15-day injured list with an oblique injury, and despite looking sharp through four innings, he was pulled after just 54 pitches. The second-year right-hander would be an intriguing streaming option while Davies is out, but given his current limitations, he doesn't have enough upside to warrant a roster move in standard leagues. He's tentatively scheduled to pitch again versus St. Louis next week.

Jameson will start Wednesday against the Brewers, Jody Jackson of Bally Sports Arizona reports.

EDGE Analysis

Jameson is moving into the rotation to replace Zach Davies after Davies was placed on the 15-day injured list with his oblique strain. The right-hander has registered a 2.16 ERA and whiffed eight hitters in his 8.1 innings of work. There are some talented arms in the Arizona system who could replace Jameson if he struggles early -- namely top prospect Brandon Pfaadt -- but it seems likely that he'll be given a few turns in the rotation to begin the year.

Diamondbacks manager Torey Lovullo announced Sunday that Jameson is moving into the starting rotation while Zach Davies (oblique) is on the injured list, Theo Mackie of The Arizona Republic reports.

EDGE Analysis

Jameson has been effective out of the bullpen for the Diamondbacks thus far with a 2.16 ERA and 8:5 K:BB over 8.1 innings in three appearances. The right-hander has worked at least two innings in each of his outings -- including four against the Dodgers on March 31 -- and he should be stretched out after competing for the fifth starter spot in the Cactus League. If Jameson pitches well over his first few outings he has a good chance to stay in the rotation even after Davies is ready to return. If the 25-year-old were to struggle, the Diamondbacks could turn to top prospect Brandon Pfaadt in the coming weeks.