As we approach Major League Baseball's All-Star break, let's examine the players who have improved their stock versus those who have struggled and decreased their value.

The New York Mets had their worst month of the season in June, going 12-15 and surrendering first place to their National League East rivals, the Philadelphia Phillies.

Who's up and who's down for the Mets as they look to reclaim the NL East crown?

Stock up

2B Jeff McNeil

The former batting champion has been carrying the bottom of the Mets' lineup since being activated from the injured list in late April. McNeil has put last year's offensive struggles behind him, with 18 extra-base hits, 26 RBI and an .817 OPS in 54 games. 

The 33-year-old has walked (21) more than he's struck out (20) across 198 plate appearances. McNeil's also batting .348 over his last seven games. 

RHP Clay Holmes

While there were rightful doubts regarding Holmes' transition into a full-time starter after being the Yankees' primary closer for four seasons, the Mets' rotation has benefited significantly from his addition.

The 32-year-old has posted a 2.99 ERA and 1.24 WHIP in 17 starts, striking out 76 batters across 93.1 innings. Holmes also has an above-average groundball rate at 53.9%, ranking in the 90th percentile in the league, per Statcast.

Stock down

3B Mark Vientos

Following a breakout campaign in 2024 in which he hit 27 home runs, Vientos has struggled mightily this season. He's slashing just .218/.282/.354 with 15 extra-base hits, 21 RBI and 57 strikeouts across 227 plate appearances. 

Vientos spent most of last month on the injured list with a hamstring strain, but is only 2-for-19 since being activated on June 27.

LHP David Peterson

Peterson's surface-level stats are solid. He's tossed 102 innings to the tune of a 3.18 ERA with a 57% groundball rate, and 10 of his 17 starts have been quality starts. However, opponents have an xBA of .272 vs. the southpaw and are hitting him hard, with an average exit velocity of 90.6 mph. 

Peterson's good luck through the first two months of the season got exposed in June, when he posted a 4.55 ERA. Although he bounced back on Thursday in a win vs. the Milwaukee Brewers, his performance likely isn't sustainable.