OF Brandon Nimmo
What he is: Nimmo is the Mets' top outfield prospect, and one of the team's best position player prospects -- along with Dilson Herrera and ahead of fellow first-rounders Michael Conforto, Gavin Cecchini and Dominic Smith. Nimmo, who turned 21 in March, has had a strong 2014 season. He hit his way out of the Florida State League (.322/.448/.458) and is hanging around at .248/.359/.416 in 59 games in Double-A. Buried beneath a low batting average in Double-A is a .168 isolated slugging percentage, which would be his best at any stop in his minor league career. In Double-A, he's kept his strikeout rate under 20 percent and walked in 14 percent of his plate appearances. He's an extremely patient hitter starting to come into his power - he's bopped a new career-high 10 home runs this year to go with 19 doubles and nine triples. In 21 games in August, Nimmo has hit a healthy .289/.372/.434 with 10 walks and 15 strikeouts.
The one real blemish against Nimmo statistically in Double-A has been his performance against lefties. After hitting .333/.435/.417 against southpaws with a 16.5 percent strikeout rate and a .414 BABIP in 72 AB in the FSL, he's slipped to .162/.311/.270 with a 25 percent strikeout rate and a .220 BABIP against same-handed pitching in 74 AB in Double-A. The answer, as is so common, is somewhere in the middle. He's probably not as good against lefties as his advanced-A numbers suggest and he's not as bad as his double-A numbers. He's made improvements against lefties and will need to continue to do so to maintain his potential as an above-average everyday guy.
Why he's going: To face more high-level competition to prepare for his MLB debut in 2015
What I'm looking for: The plate discipline will be there, but will the power? Will he hit lefties?
SS/INF Matt Reynolds
What he is: The Mets' second-round pick in 2012, the 23-year-old Reynolds has bounced back from a disappointing 2013 season by beating up Double- and Triple-A pitching. Across the minors' two highest levels, he's hit .347/.411/.459 with a .423 BABIP this year with an 19 percent strikeout rate and a 10 percent walk rate. At the beginning of August, this piece examined the statistical underpinnings for Reynolds' breakout and sought to normalize his BABIP for league environment and his batted ball profile.
Why he's going: Same as Nimmo, to get some more plate appearances against top competition to put himself in a better position to contribute in 2015, in Reynolds' case, most likely as a utility guy.
What I'm looking for: More secondary skills and where he plays.
What's interesting about Reynolds' assignment to the AFL, is that generally guys brought up to the big leagues skip the desert, so this suggests that Reynolds will miss out on a September call-up. Sure, the Mets want to use September to continue their extended look at Wilmer Flores at shortstop. Sure, Reynolds, who was drafted in 2012, is not Rule 5 eligible this year, and would not need to be added to the 40-man roster until next year. Sure, the Las Vegas 51s are going to the playoffs which could run through the second week of September. So, the team has roster flexibility reasons, developmental and minor league pennant reasons to avoid the big leagues for him for now. On the other hand, the Mets played Tuesday down two starting infielders in Daniel Murphy and David Wright. If either needs to go to the DL, Reynolds might get his first taste of the big leagues sooner than planned.
RHP Cory Mazzoni
What he is: An oft-injured second-round pick from 2011. He's a three-pitch guy with a splitter for a changeup who works in the low 90s -- about 90-92 -- although he can reach back for more in a big spot. Like many of the Mets' recent collegiate draftees, he's a "strikethrower"; in 31 2/3 innings in August, he's fanned 31 and walked just two.
What he's doing: Getting more innings. Mazzoni, to this point has made just eight starts in Triple-A this year. He left his final spring training tune-up with an apparent triceps strain that was later reclassified as a lat strain. It kept him on the shelf until late June, when he began a rehab tour in the GCL that took him through St. Lucie and Binghamton for two starts each before reaching Triple-A on July 18. Mazzoni, who's a little slight at 6'1", has dealt with a number of medical issues in the last three years: including elbow neuritis in April, 2013, arthroscopic surgery on his knee in August 2013 and some missed starts in late July 2012 with a finger issue.
What I'm looking for: I think Mazzoni's stuff plays better out of the bullpen, but mainly he's going to the AFL to extend his season and make up for missing two and a half months of the season.
RHP Paul Sewald
What he is: The Mets' 10th-round pick out of the University of San Diego in 2012 who signed for a team-friendly $1,000, and has been an effective reliever in Single-A in 2013 and 2014. The Mets just promoted Sewald to Double-A this week. He throws strikes, and attacks the strike zone with a fastball around 90 mph.
What he's doing: Proving he has the stuff to merit an Opening Day assignment to Double-A in 2014 and filling out the AFL roster.
What I'm looking for: An ERA under 5.00.
RHP Julian Hilario
What he is: A 24-year-old right-hander with bad body who throws hard (like can get up to 96), but has little idea where it's going. In 48 2/3 innings this year in the Florida State League, he's walked 34 guys, a walk rate of 15 percent.
What he's doing: Trying to prove he's better than his 5.73 ERA in the FSL and ready for Double-A in 2015.
What I'm looking for: An ERA under 6.00.
RHP Rob Whalen
What he is: The Mets' 12th-round pick in 2012, Whalen is a solidly built 20-year old with a four-pitch mix. He mostly works around 88-90, but he has been up to 91 with his fastball in games recently. He throws his curveball regularly early in counts and has been using his slider as a put-away pitch. It's a winning recipe in Single-A, certainly.
What he's doing: LIke Mazzoni, extending a season that has been truncated by injury. A cut on his pitching hand became infected during a start on May 1, and kept him out until July 23, so he's made just 10 appearances for Savannah this year.
What I'm looking for: Survival. Whalen will start 2015 in advanced Single-A.
Last year, the Mets sent C Cam Maron, 3B/1B Aderlin Rodriguez, OF Cory Vaughn, RHP Chasen Bradford, RHP Jeurys Familia, RHP Hansel Robles and RHP Cody Satterwhite to the AFL.
In 2012, the delegation included OF Darrell Ceciliani, INF Daniel Muno, OF Cesar Puello, RHP Ryan Fraser, LHP Chase Huchingson, LHP Adam Kolarek, and RHP Greg Peavey.