Roto Roundup: Felix Hernandez, Jordan Zimmermann, Clayton Kershaw and others.

Prospect Buy and Hold

With the news that Gregory Polanco will be called up on Friday.....oh wait, no he won't. It seems the Pirates were upset that the news of the call up were leaked before they could announce it to the world, so they decided to wait. So Pirates. We had a few other prospects called up this week, including Astros first base prospect Jon Singleton, Rockies starterEddie Butler and Orioles starter Kevin Gausman, who is pitching today.

Here is Jason Hunt's list of the players who could be called up in the next few weeks, or later this season. His weekly Buy and Hold series takes a look at players you should look at grabbing off your league waiver wire before they are called up, and before your league mates grab them.

Buy and Hold: Week 10

Top 25 Fantasy Prospects for 2014

Matt Mattingly offered Fake Teams readers his midseason Top 25 Fantasy Prospect rankings on Sunday morning, and his rankings will make Cubs fans very happy.

Top 25 Fantasy Prospects

Matt also offered readers his take on which prospects will be called up after the silly Super Two deadline:

Super Two Deadline: Prospect Call Ups

Felix Hernandez dominates the Rays

The Rays have been struggling to win games and score runs of late, so it comes as no surprise that Mariners ace Felix Hernandez had his way with them on Sunday afternoon. King Felix thoroughly dominated the Rays, shutting them out for seven innings, giving up just 4 hits, a walk and striking out 15 in the Mariners 5-0 win. He did not figure in the decision, as the Mariners gave him zero run support, but scored five runs in the ninth inning.

The 15 strikeouts were a career high, and he is now 8-1 with a 2.39 ERA, 1.92 FIP, a 2.41 xFIP, a 1.01 WHIP and a 106-17 strikeout to walk rate in 98 innings this season. He has given up more than two runs in a game in just 3 of his 14 starts, and has given up one run or less in five of those starts. He is striking out just under ten batters per nine, walking 1.5 batters per nine and inducing ground balls at a 53% clip thus far, and is one of the leading candidates for the American League Cy Young award right now.

For more on Hernandez's outing, check out Lookout Landing, SB Nation's Mariners fan site.

Round'em Up

Nationals starter Jordan Zimmermann has struggled of late, giving up three runs or more in four of his five May starts. June has been much kinder to Zimmermann as he has yet to give up a run in his two June starts, including Sunday's dominating performance vs the Padres. He tossed a complete game, two-hit shutout, walking none and striking out 12 in the Nationals 6-0 win. Zimmermann improved his record to 5-2 with a 3.17 ERA, 1.24 WHIP and a solid 66-14 strikeout to walk rate in 76.2 innings.

Dodgers ace Clayton Kershaw appears to be getting back to the dominating starter that he is. After giving up 7 runs in 1.2 innings vs the Diamondbacks back on May 17th, Kershaw has won three of his next four starts, including Sunday's start vs the Rockies. Kershaw limited the Rockies to just one run on 3 hits, no walks and 9 strikeouts in 5 innings in the rain-shortened 6-1 win. Kershaw is now 5-2 with a 3.17 ERA, 1.03 WHIP and a 64-7 strikeout to walk rate in 48.1 innings thus far. Over his last four starts since May 17th, he has put up 36-4 strikeout to walk rate in just 26 innings of work.

Kershaw's record may not show it, but he is actually having a much better year than last year's Cy Young Award season. He has improved his strikeout rate from 8.85 K/9 to 11.92 K/9, reduced his walk rate from 1.98 BB/9 to 1.30 BB/9, and improved his ground ball rate from 46% to 58% in his eight starts this season.

Astros first base prospect Jonathan Singleton has been struggling to make contact in his first week in the big leagues, as he has struck out in 10 of his 25 at bats thus far, but when he is making contact, he is making it count. On Sunday, Singleton went 2-6 with a double and a grand slam in the Astros 14-5 win over the Twins. Singleton has hit in four of his six games, with two of those hits landing over the outfield wall. It will be fun to watch he and George Springer in the middle of the Astros lineup over the next five years.

Angels outfielder Josh Hamilton had a nice day at the plate on Sunday, going 2-4 with a double and 3 RBI in the Angels 4-2 win over the White Sox. Hamilton enjoyed a good weekend at the plate going 7-12 with 2 runs scored and 4 RBI, and is now hitting .400-.474-.660 with 3 home runs, 10 runs scored and 11 RBI in 50 at bats. Hamilton missed about 6 weeks due to a thumb injury suffered when sliding head first into first base.

I found it interesting that Cardinals manager Mike Matheny used closer Trevor Rosenthal in the ninth inning of Sunday's 5-0 win over the Blue Jays. Rosenthal gave up a hit and struck out one in the scoreless inning. He had not made an appearance since June 4th, so maybe that explains his use, but I wonder if he is on thin ice after blowing his last save opportunity.

Maybe I was too low on Braves outfielder Justin Upton in my preseason rankings. Upton is having a terrific season at the plate, a season we have all been waiting for him to put up since his breakout season in 2011. On Sunday, Upton went 1-2 with 2 walks, 2 runs scored, a home run and 2 RBI in the Braves 6-5 loss to the Diamondbacks. Upton raised his slash line to .291-.370-.554 with 14 home runs, 32 runs scored, 36 RBI and 6 stolen bases in 6 attempts, and is on pace for 37 home runs, 16 stolen bases and 96 RBI this season.

Fantasy Rundown

For more fantasy baseball (and football) news and rankings, make sure you check out Fantasy Rundown, your one stop for all the fantasy news you need on a daily basis.