SEATTLE — Alex Jackson was once thought to be the solution for the Mariners’ long quest to find a potent right-handed hitter that could play a corner outfield spot. In three seasons in the Mariners’ minor league system, there were minimal signs of that projected prospect. Now, Jackson is a member of the Atlanta Braves.

On Monday evening, Seattle general manager Jerry Dipoto continued his traditional offseason roster tweaking by completing a trade with the Braves, acquiring right-handed pitchers Rob Whalen and Max Povse from Atlanta in exchange for Jackson and a player to be named later. To make room for Whalen on the 40-man, reliever Ryan Weber was designated for assignment.

“This move gives us two young, polished pitchers who immediately bolster our starting pitching depth, while adding to our roster flexibility,” Dipoto said.

But it also speaks to how far Jackson had fallen as a prospect in the organization’s view. Considering his talent, he’s been another disappointing first-round selection for an organization that hasn’t had a stellar track record for making first-round picks, dating back to the mid-1990s.

Jackson, who turns 21 on Christmas Day, was taken with the sixth overall pick of the 2014 draft. He was immediately considered one of Seattle’s top prospects. But that potential was only shown in flashes without much consistency. He was hampered by injuries and adjusting his approach. Over 192 games minor league games, none above the Low-Class A Level, Jackson hit .233 with a .727 on-base percentage with 223 strikeouts.

In an attempt to reset his progress, the new regime under Dipoto and director of player development Andy McKay decided to keep Jackson at extended spring training to start the 2016 season. They wanted him to meet a certain level of criteria in performance, preparation and attitude before letting him join Class A Clinton. Jackson was sent to the LumberKings in late May. In 92 games, he hit .243 with 20 doubles, a triple, 11 homers and 55 RBI.

With the trade earlier in the week that sent Taijuan Walker to the Diamondbacks, the Mariners were in need of some pitching depth beyond Felix Hernandez, Hisashi Iwakuma, James Paxton, Ariel Miranda and Nathan Karns. Whalen and Povse will provide some immediate depth. But it’s likely the Mariners will also look at other more experienced options on the free agent market as well.

Whalen, who turns 23 on Jan. 31, made five starts for Atlanta last season, posting a 1-2 record with a 6.57 ERA. His season ended in late August with a trip to the disabled list with shoulder fatigue. Whalen started the 2016 season with Class AA Mississippi, posting a 7-5 record with a 2.49 ERA in 18 starts. He had 94 strikeouts and 37 walks in 101 1/3 innings pitched. Over his final 10 starts with Mississippi before being promoted to Class AAA Gwinnett, Whalen went 5-1 with a 1.62 ERA. He made three starts with Gwinnett before joining the Braves.

Povse, 23, went 9-6 with a 3.36 ERA in 26 starts combined between Class A Carolina and Class AA Mississippi with a career-high 139 strikeouts. Standing 6-foot-8 and 250 pounds, he cuts an imposing figure on the mound. He has a fastball with plenty of sink that sits around 93-94 mph but can touch 96 mph. A third-round pick out of the University of North Carolina-Greensboro in 2014, Povse has made 54 starts and one relief appearance in the minors, posting an 18-13 record with a 3.59 ERA. He was rated Atlanta’s No. 20 prospect per MLB.com.

The Mariners claimed Weber off waivers from the Braves on Nov. 2.