It's that time of year. Pitchers and catchers officially reported to spring training on Sunday, and now things will begin ramping up toward the start of exhibition action in 10 days.
 
As usual, Twins Daily will be on-site in Ft. Myers with in-depth coverage of camp throughout the month of March. Over the next couple of weeks, we'll lead up to that coverage by listing and profiling our choices for the Top 20 prospects in the organization.
 
20. Jake Reed - RHP
Age: 23
2015 Stats (A+/AA): 59.1 IP, 5.01 ERA, 46/22 K/BB, 1.43 WHIP
ETA: 2017
 
After a career at the University of Oregon that featured big success after converting from starter to closer his senior year, Jake Reed was selected by the Twins in the fifth round of the 2014 draft. After signing, he made 20 appearances between rookie-level Elizabethton and Low-A Cedar Rapids and dominated with his scorching heater, piling up 39 strikeouts while allowing only 11 hits and three walks over 31 innings.
 
The Twins jumped Reed straight to Double-A for his first full season in the system, and the righty struggled immensely with the transition, allowing 28 earned runs on 50 hits in 45 innings before being demoted to Ft. Myers in August. His poor performance as a 22-year-old at Chattanooga raises alarms, but to some extent Reed was thrown right into fire.
 
This will be a crucial year for him. If he bounces back strongly there's a chance he could enter the MLB bullpen picture in August or September.
 
19. Randy Rosario - LHP
Age: 21
2015 Stats (Rookie/A): 61.2 IP, 4.52 ERA, 54/20 K/BB, 1.30 WHIP
ETA: 2017
 
When the Twins made a wave of 40-man roster additions at the end of the 2015 season, the most interesting and unexpected name in the mix may have been Randy Rosario. On the surface, there's nothing in his numbers or progression that would suggest he was at risk of being stolen away if left unprotected. Rosario has made only 48 total appearances in the minors, and at age 21 still hasn't pitched above Low-A.
 
But the lefty, who was signed by the Twins out of the Dominican Republic as a teenager in 2010, has an arm that would appeal to any baseball team. Before undergoing Tommy John surgery in 2014, he was touching the upper 90s with his fastball and complementing that with a nasty slider.
 
His lack of in-game experience (he hasn't pitched more than 13 games in a pro season) makes him a major unknown, but Rosario offers a great deal of upside and the Twins recognize that. He'll probably open the season in Ft. Myers but he's in position to rise fast if he can stay healthy.
 
18. Lewin Diaz - 1B
Age: 19
2015 Stats (Rookie): 47 G, .233/.322/.371, 4 HR, 19 R, 20 RBI
ETA: 2019
 
The Twins signed the Dominican Lewin Diaz as a 16-year-old back in July of 2013. With a $1.4 million bonus, he became the organization's biggest amateur international signing since Miguel Sano, whom they had reeled in four years earlier. At the time of the acquisition, MLB.com had Diaz ranked as the 10th-best prospect on the international market, lauding the raw power and advanced swing mechanics for his age.
 
Diaz has spent two seasons playing pro ball here in the States, and his performance gives us little to go on; the numbers have been rather ordinary (.244/.353/.409 between two levels of rookie ball) but he has also been a teenager facing largely older competition and growing into his body. Keep in mind that Max Kepler, who also signed originally as a 16-year-old from a foreign country, hit only one home run total over his first two seasons in the rookie leagues. Patience is required with these kids.
 
Ultimately, power is going to be the defining trait for Diaz, who plays first base and doesn't move especially well. We should get a better idea of his true potential in that department over the next couple of years.
 
17. Engelb Vielma - SS
Age: 21
2015 Stats (A+): 120 G, .270/.323/.306, 1 HR, 49 R, 29 RBI
ETA: 2017
 
We'll start with the bad: he can't hit.
 
OK, that's not exactly true. Engelb Vielma can put the bat on the ball, and his contact-plus-speed combination was enough to result in a respectable .270 average at Ft. Myers last year. But the 21-year-old, listed at a diminutive 5'11" and 150 lbs, doesn't hit the ball with any kind of authority. In 324 minor-league games, he has managed two home runs and 40 total extra-base hits. His career Isolated Power (SLG minus BA) in the minors is .046; for comparison, Ben Revere, one of the least powerful hitters in the majors, had a .078 mark as a minor-leaguer. Vielma's .627 OPS in the Florida State League was well below average.
 
So why does he rank so highly among Twins prospects? Vielma plays premium defense at a premium position. He is the best shortstop in the system – minors or majors – and I don't think it's especially close. When you're excellent with the glove at such a crucial spot in the field, the offensive bar is lowered substantially, thus the reason that players like Andrelton Simmons and Alcides Escobar are so highly valued even though they offer little with the bat.
 
Even accounting for that reality, Vielma doesn't look right now like a guy who will hit enough to justify a starting role in the big leagues, no matter how good he is with the mitt. But he's still young and growing, so it's reasonable to hope for some development on that front. Eduardo Escobar hit four home runs total over his first four seasons in the minors, and last year he was one of MLB's best slugging shortstops.
 
16. Taylor Rogers - LHP
Age: 25
2015 Stats (AAA): 174 IP, 3.98 ERA, 126/44 K/BB, 1.35 WHIP
ETA: 2016
 
Rogers has outperformed expectations since being selected out of the University of Kentucky in the 11th round of the 2012 draft. He experienced some success immediately after joining the pro ranks, and unlike many college pitchers, his numbers haven't fallen off too much as he has climbed the minor-league ladder. Last year, in his first turn at Triple-A, the lefty posted a 3.98 ERA, 1.35 WHIP, 6.5 K/9 and 2.3 BB/9 – all more or less in line with his career marks.
 
The problem with Rogers, like many southpaws, is his extreme susceptibility against right-handed batters. At Rochester they clubbed him around to the tune of .326/.374/.457, and that doesn't exactly bode well for his chances of excelling against MLB starting lineups stacked with righties.
 
The good news is that the 25-year-old has been utterly lethal against lefty swingers, holding them to OPS figures of .402, .555, .524 and .520 in his four seasons as a pro. He looks to have a good future ahead of him as situational reliever at the very least, and could very well be a member of the Twins bullpen on Opening Day.