There are typically two main ways of acquiring players to build up a farm system: via amateur markets (the Draft and the international amateur free agent market) and via trades. That’s why MLB Pipeline waits to re-rank top farm systems until after the Draft signing deadline has passed, after the July 2 international signing period is well underway and, of course, the Trade Deadline is behind us.

The end result is the top 15 farm system rankings released on Monday. Many teams have used those mechanisms for farm system growth to their advantage, climbing into the upper half of all systems in baseball. And there are some that haven’t quite hit the top 15 but aren’t far off thanks to improvements in Minor League talent.

Here are a half-dozen teams that have improved their farm systems the most from the start of the 2019 season until now.

1. Marlins (No. 4 system): While the trades of J.T. Realmuto and Christian Yelich brought in a good amount of talent before the season began, it seems like the Marlins are getting even better at the trade game of late, bringing in Top 100 talent (Jesus Sanchez, Jazz Chisholm) at the Trade Deadline. Throw in getting JJ Bleday with the No. 4 overall pick and No. 35 overall selection Kameron Misner in the June Draft, not to mention nice steps forward by 2015 international signees Edward Cabrera and former first-rounders Braxton Garrett and Trevor Rogers, and Miami appears to be getting the whole rebuild thing right. Marlins Top 30 Prospects list »

2. D-backs (No. 5 system): Though they did trade Chisholm to the Marlins, the D-backs did get Zac Gallen back in return and they obviously added a lot of talent in the Zack Greinke deal at the Trade Deadline. The renaissance here really began with a strong 2018 Draft (with first-rounder Alek Thomas and over-slot eighth-rounder Levi Kelly having very good first full seasons to boost the system overall). This year’s Draft, with all those early picks, netted three more players in their top 15, while 2017 international signee Kristian Robinson looks like a future star. There’s not as much elite-level talent at this point, but this is as deep a system as there is, with more players with overall 50 grades (on the 20-to-80 scouting scale) than any other organizational top 30 list. D-backs Top 30 Prospects list »

3. Orioles (No. 13): Yes, there’s still plenty of work to do here, but boy have they come a long way from being close to the bottom of any organizational rankings. Any time a team can add a generational-type talent like 2019 No. 1 overall pick Adley Rutschman, it’s going to help things. The 2019 Draft also netted top 15 prospects Gunnar Henderson and Kyle Stowers. As much as anything, some previous prospects have performed extremely well, most notably 2018 first-rounder Grayson Rodriguez, who has been even better than most expected in his first full season of pro ball. The ship is slowly being pointed in the right direction and the organization’s commitment to international talent should yield dividends in the future. O's Top 30 Prospects list »

4. Giants: The Giants were almost certainly in the bottom five farm system-wise heading into the season, and while they haven’t cracked the top 15 just yet, they have an up arrow next to their name. Their last two first-round picks, Joey Bart and Heliot Ramos, are playing well together in the California League, and they were just joined in the system by new first-rounder Hunter Bishop. Marco Luciano’s stirring United States (and pro) debut gives them four players in the Top 100 for the first time since MLB.com started ranking prospects. Giants Top 30 Prospects list »

5. Rangers (No. 14): This could go in either direction, truth be told. There is so much upside talent in this system, both from the Draft (Hans Crouse, Cole Winn, Bubba Thompson), international signings (Leody Taveras, Anderson Tejeda) and trades (Sherten Apostel), that the Rangers could develop into one of the top systems in baseball in the next couple of years. Or it could go south if those ceilings aren’t reached. Adding college talent like Josh Jung and even Davis Wendzel in the 2019 Draft helps offset the mercurial nature of this group, while the emergence of Sam Huff as one of the top catching prospects in the game certainly doesn’t hurt. Rangers Top 30 Prospects list »

6. Mariners (No. 11): The first jump came courtesy of the Robinson Cano trade and was buoyed by strong first impressions by Jarred Kelenic and Justin Dunn after coming over in that deal. Both 2018 draftee Cal Raleigh and trade acquisition Jake Fraley have turned in very solid 2019 seasons as well, allowing them to jump into the organization’s top 10, while teen phenom Julio Rodriguez has not disappointed either. The last two Drafts have provided very good college pitching (Logan Gilbert and George Kirby), and they even added a pair of Top 30 relief prospects in the Deadline deals with the Nationals. Added bonus for M’s fans: Much of this talent is amassing at the upper levels, so help is on the way soon. Mariners Top 30 Prospects list »