Twitter: @RobShawSports and @BloombergSports

While it is very difficult for fantasy managers to pick up a franchise player off the waiver wire, they are rookies who can have a major impact that remain availble for the picking.  Here’s a look at four talented players in the farm system who could be worth a waiver wire pick:

Anthony Rizzo, 1B, Cubs

A former sixth round pick who has been passed around from the Red Sox to the Padres to the Cubs, it’s looking like Anthony Rizzo could be up for a promotion very shortly.  In a 49 game stint with the Padres last season, Rizzo flopped, hitting just .141 with one home run.  Now through 44 games, Rizzo is pounding the ball in Iowa with 16 home runs and a .355 average.  Considered a long-term investment, the 22-year-old Rizzo could push Bryan LaHair to the outfield within the next month.  Now that he has left San Diego and has a favorable ballpark, Rizzo is a fine speculation pick off the waiver wire.

Danny Rosenbaum, SP, Nationals

Chances are you never heard of Danny Rosenbaum.  A former 22nd round pick, the southpaw may be the most unknown dominating ace at any level of baseball.  At one point he allowed just one earned run to score over a 45-inning stretch this season at Double-A.  The 24-year-old hurler is a perfect 6-0 through nine starts this season.  He is a control pitcher that has never had an ERA higher than 2.60 in his professional career.  Rosenbaum’s never been known for his stuff, and the Nats rotation seems pretty full, but these numbers are too good to dismiss.

Julio Teheran, SP, Braves

There was consideration for Julio Teheran to make the Braves rotation coming into the season, but instead he was beat out by fellow top prospect Randall Delgado.  At Triple-A he has been something of an enigma.  His control is a tad off and he is not racking up the K’s at the rate you would expect.  Perhaps it has something to do with frustration still pitching in the minors, but a call to the Majors could happen at any moment especially with Mike Minor struggling with the Braves.

Trevor Bauer, SP, Diamondbacks

The Trevor Bauer watch continues in Arizona, as the Diamondbacks top prospect was recently promoted to Triple-A after dominating Double-A with 7 wins in 8 starts.  In his first two starts since the promotion, Bauer has fanned more than a batter per inning while allowing just two runs in 13 innings.  The Diamondbacks have a few top prospects in the farm system and have to be pleased with the play of Wade Miley this season.  For now Patrick Corbin is holding down the fifth spot in the rotation with Daniel Hudson injured, but Bauer is likely on call.