Updated top 250 fantasy baseball rankings

Hot corner, hot new fantasy stars.

Third base has long had the perception of being a "deep" position, perhaps the product of four household names -- Adrian Beltre, Evan Longoria, Aramis Ramirez and David Wright -- managing multiple top-50 seasons (overall, not simply at the position) during the four-year span from 2009 to 2012. The truth is that the name brands often exceeded the players' true value; injuries and frequently disappointing stretches by players such as Longoria, Wright, Ryan Zimmerman and Pablo Sandoval often made third base the position at which you might waste a large amount of your draft resources.

All that's changing.

As of the morning of July 1, four third basemen placed among the top 13 overall on our Player Rater: Todd Frazier (4th), Manny Machado (8th), Nolan Arenado (11th) and Josh Donaldson (13th).

Now run the Player Rater's "Last 30" split: Machado and Arenado occupied the top two spots, and joining them and Frazier among the top 10 overall players was Philadelphia Phillies rookie Maikel Franco.

Third base is once again a deep position, except the names of the leading men have changed. Three of my top five third basemen -- including two of the three who entered my top 20 overall players -- are younger than 25. The young stars have arrived, and they should provide more rest-of-season stability than their older counterparts, many of whom continue to tumble in the ranks.

Arenado: He's on some kind of hot streak of late, batting .302/.317/.724 with 13 home runs, 35 RBIs and 25 runs scored in his past 30 games, a remarkable performance when looking at that narrow gap between his batting average and on-base percentage and recognizing that Arenado is one of the more aggressive swingers in baseball. To that point, his 4.2 percent walk rate ranks in the 88th percentile and his 56 percent swing rate in the 97th percentile, among batting-title-eligible hitters. But here's what's so remarkable about Arenado's season: He's a .297/.338/.662 hitter in his road games. That's a whopping .366 isolated power.

Anyone care to guess how many players have managed .366-plus isolated power in all their games of a single season of 250-plus plate appearances -- roughly half of what's needed to qualify for a batting title in a given year -- in history? Thirteen players for a total of 29 seasons. Again: ever.

What has driven Arenado's breakthrough has been an extension of what fueled his strong finish to 2014: He continues to drive the ball with greater authority, his fly ball rate rising from 33 percent in 2013 to 37 percent last season to 44 percent this season. While doing that, he hasn't changed a key element to his game, his contact ability when he does swing at non-strikes, as his 38 percent miss rate on those swings isn't far removed from the league average of 36 percent. Yes, it's time to call Arenado a top-20-overall talent, and as colleague Eric Karabell also wrote, the first round is absolutely in the discussion for 2016 drafts.

Machado: If Arenado's past month has been this exceptional, then what has Machado's been? He has been the higher performer on the Player Rater, after all. That's entirely thanks to Machado's stolen bases -- 11 to Arenado's zero -- though Machado has made similar adjustments that make him a bona fide top-20-overall player for the remainder of 2015 (and beyond).

Consider that in Machado's final 32 games of 2014, he lowered his ground ball rate to 46 percent and increased his fly ball rate to 31 percent; this season, his numbers in those categories are 43 and 37 percent, respectively. Just as Arenado has done, Machado is driving the ball with greater authority, but it's his aggressiveness on the base paths that is so encouraging, considering the multiple knee surgeries he has on his résumé. I've made the case previously that he's a 20/20 candidate for sure, and there's a realistic chance he'll finish with 30/20 numbers.

Frazier: Though not as young as the previous two -- he's 29 -- Frazier enjoys a similar parallel in that he's also hitting fly balls at a greater rate, 45 percent, which is up from his 39 and 32 percent rates of 2013 and 2014, respectively. It reminds me of his burst-onto-the-scene 2012; he had a 47 percent fly ball rate then, which fueled my hopes he might be a sneaky, 30-homer bet in 2013. (Alas, two years too early.) Frazier fans probably enjoy his stolen base contributions, and indeed those drive his fantasy value, but the real reason for his ascent in the rankings below has been his power, which grants him a legitimate chance at 40-plus homers -- to go along with 15 or so steals -- by season's end.

New ESPN position eligibility

The following players added new position eligibility within the past week. As a reminder, position players need to appear 10 times at a new position to gain in-season eligibility, while pitchers need to make three starts to earn starting-pitching eligibility or five relief appearances to earn relief-pitching eligibility.

Derek Dietrich (3B), Danny Espinosa (3B), Nick Franklin (1B), Joey Gallo (OF), Enrique Hernandez (OF), Jonathan Herrera (3B), Brock Holt (2B), Travis Ishikawa (OF), Ben Paulsen (OF), Donn Roach (SP), Ryan Rua (OF).

The following players are within two games of earning new eligibility, with their total games played noted at the listed position: Joaquin Arias (SS, 8 games), Tim Beckham (SS, 9 games), Andres Blanco (2B, 8 games), Pedro Ciriaco (3B, 9 games), Logan Forsythe (3B, 8 games), Hector Gomez (3B, 9 games), Marwin Gonzalez (3B, 8 games), Alex Guerrero (3B, 9 games), Corey Hart (1B, 8 games), Brock Holt (SS, 8 games), Chris Johnson (1B, 8 games), Pete Kozma (2B, 8 games; 3B, 8 games), Rey Navarro (2B, 9 games), Kris Negron (OF, 9 games), Luis Sardinas (2B, 8 games), Cory Spangenberg (3B, 9 games), Justin Turner (1B, 9 games).

Going-forward rankings: Week 13

Listed below are my updated, going-forward rankings. These are based upon an ESPN standard league of 10 teams and Rotisserie 5x5 scoring. Click here to see these rankings sorted by position.