MESA, Ariz. -- A day off on Monday for the Chicago Cubs' major-league team gives us a chance to catch up with what’s happening on the minor-league side. Though they’ve graduated a crop of top prospects to the big-league club, their farm system is still highly ranked as ESPN.com’s Keith Law has them fourth in all of baseball.

Jason McLeod, the Cubs' vice president of player development and amateur scouting, sat down with us over the weekend to discuss some of the next crop of players who are on the rise.

What’s been the key for catcher Willson Contreras? How did he make the transition from infielder to highly touted catching prospect?

Jason Mcleod: When we came here in 2012 he was a long ways from where he is now. He was very enthusiastic and passionate so there were actually a lot of things behind the plate that had to be calmed down. He was a high-energy player who didn’t know when to slow the motor. He loved showing off his arm. He would back-pick a lot and throw balls down the line. So a lot had to be done to calm him down. You loved the passion because he worked hard from Day 1, but it’s been a continual process with him.

In my opinion what clicked was playing in the Venezuelan Winter league in 2014 when he was around veteran guys down there. When he came to spring camp last year he talked about that experience and how good that was for him. We saw a different guy last year and it carried over to his season. There was a more mature approach to the way he was going about things. We’re lucky for it because he was Rule 5 eligible the year before. Anyone could have had him for $50,000 and now he’s one of the more sought-after prospects.

Third-base prospect Jeimer Candelario was great during batting practice even before games started and then hit everything in sight when he got the chance to play. What’s clicked for him?

JM: It’s funny. He played with Willson Contreras in Boise in 2012 and coming out of that year you could have easily said Contreras has too far to go but Candelario looked great. He was an 18-year-old switch-hitter who controlled the zone, but fast forward a year and things were reversed. He had to learn how to deal with failure after he had that tough year in Daytona (High Single-A) and we had to send him back to Kane County (Low A). He grew up. I had some questions on his fitness, which way was it going to go. He’s worked so hard defensively. He’s made one of the biggest turnarounds on the defensive side over the last couple of years for me. I would not have said two years ago this guy is playing third base in the big leagues, but now I can say it with conviction. He can do it.

Catcher Willson Contreras has come a long way since starting with the Cubs as a young, over-eager player in 2012, said Jason Mcleod, the Cubs' vice president of player development and amateur scouting. Tony Farlow/Four Seam Images/AP Images

This is no surprise, of course, but it sounds like the common thread with these guys and also a pitcher you drafted who had Tommy John surgery is patience. You have to have patience in this game. Contreras and Candelario have been in the system since they were 17.

JM: No doubt. We all understand it. When you draft a young Latin player or a high school player, you know right then we’re looking at minimum four years, likely five years. So we all know that going into it, but as you get into the player-development path you do start to worry about the timeline when you see struggles even though you know they’re coming. When they’re doing well you don’t think about them being a year ahead or anything, but when they’re struggling you start to worry. The player plans help us. It allows us to step back and say ‘we built this plan to have a 3-4 year trajectory’ so we have to come back to those plans.

There’s always a guy or two in the low minors that lights up the Internet when he’s mentioned. Sixth-round pick and Tommy John guy Dylan Cease might be the guy of the moment. He’s lighting up the radar gun, huh? At 99-100 mph?

JM: The one thing about that whole Tommy John process is it allows them to strengthen their body overall and it allows them to work on mechanics. Dylan was a kid out of high school that I would not say had the cleanest mechanics. What I’m happy with him is his total body strength, especially his upper body. He worked hard through the rehab process and has cleaned up his delivery. He has a special arm. It’s really easy velocity. That’s exciting, especially when you see the power to the curveball when he throws it. But he has 25 innings of rookie ball under his belt. This is going to be a big, full season for him. We’re going to take the reins off him so to speak.

What’s that like in the draft room -- taking a guy with Tommy John surgery? It’s hard enough to make it as a prospect, but then he has this to overcome.

JM: The good thing is he dropped and we were able to take him late. For us it’s a calculated risk and a chance to hit on a big-time prospect in the sixth round. It’s a lottery ticket. Any high school player, especially pitchers with Tommy John, are a lottery ticket. But the payoff could be tremendous with him.

Who else is jumping out at you during camp?

JM: Last year’s draft class. Those guys have all impressed. (First-round pick) Ian Happ made a lot of improvements as he transitions full time to second base. Donnie Dewees has shown great athleticism. Bryan Hudson has turned a lot of heads. He uses his (6-foot-8) height to get a good angle to his fastball. D.J Wilson has been the buzz amongst staff just because he’s such a dynamic athlete. Eloy Jimenez has been super impressive at the plate. Eloy might be one of those guys that really bursts onto the prospect scene this year. People already know about him because of the bonus he got and his short season, but the at-bats are so much more mature then you would expect from a 19-year-old. His swing is powerful but balanced. If you go to South Bend (Class-A) it’s going to be a prospect-laden team.

So I don’t know if anxious is the right word, but are you curious to see which pitcher you’ve drafted since coming to the Cubs is the first to actually throw a pitch for the major-league team?

JM: Of course. I think we’re on the verge of it. We’ve taken the volume approach after the first round. There’s been some bumps in the road for Pierce Johnson (2012) but he’ll be at Triple-A this year. Duane Underwood (2012) had a little setback. He’ll be a couple of weeks behind at Double-A. That group that’s been together from Boise to South Bend to Myrtle last year, they’ve all performed well but one of them needs to take that bigger step forward. Ryan Williams (2014) is also right there. Pencil him into the Triple-A rotation. He’s like Kyle Hendricks was; just keeps moving up and improving. He’s so efficient. A big test will be the Pacific Coast League. It’s a great hitter’s league. He’ll face a lot of guys that have been in the big leagues before. Last year he was so quick with his outs. It might not happen the same way at Triple-A.

How excited are you that people like my colleague Keith Law still have your farm system so highly rated despite 4-5 players leaving and making it to the majors?

JM: Well, it comes down to depth. It’s no longer about one minor-league team like in Daytona or wherever. Now I go to a different field each day to watch each team. There is depth all over. We didn’t have that a few years ago. There will be a group at South Bend then at Myrtle and at Iowa and Tennessee. It’s exciting.

What kind of challenge is this draft without picking in the first or second round?

JM: It’s going to be real weird not choosing on the first day. I’ve never had that before. Our challenge is finding good players in rounds 3 and beyond. I rolled out a spreadsheet to our scouts with good players from the past who have come out of there. The percentages go lower when you go down from each round, but the fact is there are still a lot of players who are impactful. We need to find those guys. In some ways we can focus even more because we don’t need to look at the top guys around the country. We’ll be ultra-prepared.