With the non-waiver trade deadline behind us, non-contenders will start to move on from their mediocre veterans. Over the coming weeks, we'll see a few call ups in preparation for September expanded rosters.

These early moves will be made to get an extra look at a select few before rosters are flooded with inexperienced players. Keep an eye out - some of these seemingly innocuous promotions can be big adds for dynasty owners.

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Dynasty Advice for Week 19

Nick Senzel - Cincinnati Reds 

In many dynasty leagues, it's much to late to acquire Senzel. The Reds first round draft pick is posting gaudy numbers in Low-A - .331/.438/.593 with six home runs and 12 steals in 144 plate appearances. His 15.3 percent walk rate and 17.4 percent strikeout rate also speak to dominance of the level. Statistically, he's ready for a promotion.

The 21-year-old may be the first impact player to reach the majors from the 2016 draft, following a similar path to Alex Bregman and Andrew Benintendi. Although he's shown good speed on the bases, he doesn't profile as a base thief in the majors. The Reds are aggressive so expect about 10 steals. He'd be closer to the three steals on a more conservative club.

His power, quality of contact, and plate discipline should transfer up the ladder. It's not uncommon to see walk and strikeout rates go in the wrong direction as a player reaches the upper minors. The jump from High-A to Double-A can be particularly large as is the move from Triple-A to the majors. Ask basically every Astros prospect to try the transition this year - they've all hit speed bumps with spikes in their strikeout rate.

While we may see Senzel next year, he's unlikely to make a fantasy impact until 2018 or later.

Kyle Wren - Milwaukee Brewers

The best places to find dynasty bargains are on bad major league rosters. These teams have to give playing time to somebody, and they'll often cast a wide net in their search for potential talent. The Brewers are one of the best sources this season with Jonathan Villar, Hernan Perez, Junior Guerra, Zach Davies, and Tyler Thornburg all going from freely acquirable in almost any fantasy league to actual quality assets.

Despite possessing about a hundred thousand outfield prospects, the club hasn't had much success developing a name to slot alongside Ryan Braun this year. Domingo Santana was supposed to be the guy, but he's consiering an elbow surgery. Kirk Nieuwenhuis, Ramon Flores, and Keon Broxton haven't shown more than sixth outfielder skills.

Enter Wren. The 25-year-old lefty swings a light bat. His current .102 ISO at Triple-A is his highest since his 2013 debut. And that's with the help of Colorado Springs. Of more value is his plus speed and quality plate discipline. He has 25 stolen bases and more walks than strikeouts through 384 plate appearances split between Double- and Triple-A.

Milwaukee has a wave of real prospects on the horizon. Before they arrive, the Brewers should give Wren a brief window to perform.

I compiled a list of all 2016 hitters with attributes similar to Wren. It's not very encouraging. Some like Brett Gardner, Adrian Gonzalez, and Hyun-soo Kim have too much power to be a comp. Present day Ichiro Suzuki is a good example of the possible upside. A faster, less powerful Nick Markakis might work, and Wren isn't entirely dissimilar to Tony Kemp (recently recalled by the Astros). The point of the exercise is to show that few players succeed with Wren's profile and even fewer start. Still, he could be an interesting, temporary speed play with OBP skills.

Rapid Fire

Rowdy Tellez - Toronto Blue Jays

Tellez has been on the prospect radar for years. Now he's rewarding those who believed in him with a .299/.389/.515 slash and 16 home runs in 391 Double-A plate appearances. Although he has four stolen bases, he's the type of player who can only take bags when the pitcher forgets he's out there. With Edwin Encarnacion and Jose Bautista likely headed for greener pastures this offseason, Tellez will soon be knocking on the door for major league reps.

Jairo Beras - Texas Rangers

Beras was once closely linked to Nomar Mazara as a breakout candidate. Mazara clicked while Bera continues to move level by level. Still, there's nothing wrong with a 20-year-old bopping 17 home runs in 345 plate appearances at High-A. The outfielder has serious warts in his profile including a 28.4 percent strikeout rate and .293 OBP. He's been particularly good since July 17 - .346/.368/.808 with seven home runs in 57 plate appearances.

Francisco Mejia - Cleveland Indians

Forty-seven. That's the duration of Mejia's current hit streak, split between Low- and High-A. Mejia is a switch-hitting catching prospect. He's expected to stick behind the plate as an average or better defender. The 20-year-old is still a couple years from the majors, and he doesn't figure to be a huge source of fantasy production. There are several ways for him to breakout beyond his current aggressive, medium-pop profile. Better plate discipline or an increase in power could lead him to be a top catcher.

Dalton Pompey - Toronto Blue Jays

An injury to Kevin Pillar could open a short term opportunity for Pompey. The 23-year-old has always reminded me of Jackie Bradley Jr. Prior to this year, I thought of that as a bad thing. Pompey has a little too much swing-and-miss at the major league level. Early in his career, he'll rely on speed and plus defense to remain in the lineup. The switch-hitter does have the necessary size to eventually hit for some power. Like Bradley, there's big breakout potential for sometime in the future. Not all prospects develop in a clean and mannerly fashion. The late bloomers are the fantasy gold.

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