SAN DIEGO -- Depending on what the Mets do before the July 31 non-waiver Trade Deadline, shortstop Amed Rosario's promotion to the Majors could be weeks or even days away. For now, he'll have to settle for being one of the headliners on MLB.com's midseason Top 100 prospects list.

Rosario vaulted from his preseason rank of No. 5 all the way to No. 2, trailing only recent White Sox prospect Yoan Moncada on the list released this week. Moncada has since joined the White Sox. The Mets landed one other prospect on the midseason list: first baseman Dominic Smith, who also received a sizeable bump from No. 63 to 41.

The ranking of baseball's top prospects is done by MLBPipeline.com Draft and prospect experts Jonathan Mayo, Jim Callis and Mike Rosenbaum, who compile input from industry sources, including scouts and scouting directors. It is based on analysis of players' skill sets, upsides, proximity to the Majors and potential immediate impact to their teams. Only players with rookie status are eligible for the list. Players who were at least 23 years old when they signed and played in leagues deemed to be professional (Japan, Korea, Taiwan, Cuba) are not eligible.

• Midseason Top 100 Prospects list | Mets' Top 30

Rosario, who returned to the Las Vegas lineup Monday following a week-long absence due to illness, is batting .329 with seven home runs, seven triples, 18 doubles and 17 steals in 88 games at Triple-A. If the Mets succeed in trading Asdrubal Cabrera prior to the Deadline, they could shift Jose Reyes to third base and promote Rosario at that time.

"I'm 100 percent ready," Rosario said earlier this month at the SiriusXM Futures Game. "But it's whenever God's ready. He's got a plan for me."

Playing all season alongside Rosario, Smith has also thrived in the desert, batting .337 with 15 home runs in 100 games. Scouts see Smith, like Rosario, as a potential Gold Glove-caliber defender.

Beyond those two, first-round Draft pick David Peterson made his Pipeline debut at No. 3 on the Mets' Top 30 midseason prospects list. A left-handed pitcher from the University of Oregon, Peterson has yet to make his professional debut. Second-round pick Mark Vientos also made the Mets' midseason list, clocking in at No. 13.

Other notables on the Mets' midseason Top 30 include right-handed pitcher Merandy Gonzalez, who jumped from 15th to ninth after going 12-2 with a 1.54 ERA over two levels; right-hander Jordan Humphreys, a former 18th-round Draft pick whose 10-1 record and 1.79 ERA vaulted him from unranked to No. 16; and right-hander Chris Flexen, whom the Mets plan to call up to make his Major League debut Thursday in San Diego. Flexen jumped from No. 29 in the preseason to No. 17 now.

"He's got a good arm," Mets manager Terry Collins said of Flexen. "Good movement on his fastball, keeps the ball down. So I'm anxious to see him pitch, really. There's some nice talk about him."