Cesar Puello

The Marlins announced Monday that they’ve officially promoted top prospect Isan Diaz for his MLB debut (as had been previously reported), recalled Lewis Brinson from Triple-A New Orleans and selected the contract of right-hander Robert Dugger. Miami also placed infielder Neil Walker (sprained index finger) and outfielder Cesar Puello (left hip flexor strain) on the 10-day injured list, activated righty Ryne Stanek for his team debut and optioned right-hander Kyle Keller to New Orleans.

In Diaz, the Marlins will get their first look at one of the key pieces in the Christian Yelich blockbuster. Diaz currently ranks between 86th and 90th on the midseason top prospect rankings of MLB.com (86), Fangraphs (89) and Baseball America (90). He’s clobbered Triple-A pitching at a .305/.395/.578 clip, belting 26 homers, 21 doubles and two triples along the way. Originally drafted as a shortstop, he profiles better at second base from a defensive standpoint, and the Marlins hope he can be a long-term piece in the infield. Scouting reports generally suggest that his plus raw power and solid plate discipline give him a reasonable chance of being an offensive-minded everyday second baseman.

Brinson, of course, was the headliner in that Yelich swap but has yet to cement himself as a regular in the Miami outfield in parts of two seasons with the club. Since his most recent demotion to Triple-A, though, Brinson has turned in a .270/.361/.510 batting line with 16 home runs and 16 steals. That only translates to nine percent better than the league average in the ridiculous Pacific Coat League hitting environment (109 wRC+), but Brinson’s solid productivity has earned him another look. Strikeouts continue to be an issue (100 in 339 Triple-A plate appearances), but he’s demonstrated the speed and power that have long made him such an intriguing prospect.

Dugger, meanwhile, came to the Marlins in the trade that sent Dee Gordon to the Mariners. He began the season with 70 2/3 innings of 3.31 ERA ball with 9.3 K/9, 2.7 BB/9, 0.76 HR/9 and a 45.6 percent ground-ball rate in Double-A. Like so many pitchers, Dugger has been blown up in Triple-A, with a 9.34 ERA and seven home runs allowed in 35 2/3 innings since a midseason promotion. (Generally speaking, onlookers should take Triple-A stats with more of a grain of salt than ever before, given the bloated offensive numbers throughout the league.) That’s not to say that Dugger is a premium prospect, however. He ranks near the back of Miami’s top 30 prospects (24 at MLB.com, 27 at Fangraphs) and is most optimistically viewed as a back-of-the-rotation starter, though scouting reports on him also point to a possible future in relief.

It’ll also be interesting to see how Miami ultimately opts to utilize Stanek, whom they acquired alongside prospect Jesus Sanchez in a trade sending righties Nick Anderson and Trevor Richards to the Rays last week. Stanek has been the Rays’ most prolific opener since the team adopted that tactic last season and generally enjoyed favorable results. In 122 innings from 2018-19, Stanek has recorded a 3.17 ERA with 10.5 K/9, 3.5 BB/9 and 1.1 HR/9.

Stanek has pitched in late-inning situations in addition to his work as an opener, and the general fluidity of the Miami bullpen situation could serve as an avenue for Stanek to receive some save opportunities. The Marlins traded closer Sergio Romo to the Twins, and Anderson (traded for Stanek) was the presumptive heir apparent in the ninth inning. Drew Steckenrider has experience in the role but has been injured much of the season. Stanek, meanwhile, boasts a fastball that averages better than 97 mph and can reach triple-digit velocity readings, so he certainly has prototypical closer’s stuff if Miami chooses to try him at the end of games rather than the beginning.