Over the weekend, Bryan advised you on some first half performers who are on the verge of overstaying their welcome. Today I’ll be inverting that exercise and looking at some players who could be difference makers down the stretch.

While the following players aren’t likely to be found on the waiver wire, they should all have reasonable price tags on the trade market.

Mark Reynolds, 3B, Baltimore Orioles

It’s true that Reynolds can be maddening at times. He’s one of the most inconsistent players in baseball as he’s just as likely to hit .260 as he is to hit under .200, a feat he accomplished last year. With an average of .223 so far this season, owners may be willing to sell his services at a discounted price.

The shrewd buyer in you should take note of this opportunity. Despite Reynolds’s struggles in the batting average department his 20 home runs are the most hit by any third baseman not named Jose Bautista. Reynolds is also walking at the highest rate of his career and he has cut his strikeout percentage from 35.4 percent last year to 28.6 percent this year, the first time in his career it has been under 30 percent. I would also expect his batting average to improve as his BABIP of .258 is well below his career BABIP of .314.

With Reynolds mired in a 5-for-35 stretch now is the perfect time to acquire his services. A hot streak is on the horizon and with his improved plate discipline it’s not out of the question that the hot streak will last until the end of the season. It’s also important to note that with Vladimir Guerrero on the DL, Reynolds will move up in order and have more RBI opportunities.

Corey Hart, OF, Milwaukee Brewers

Hart was a wanted man in the the preseason as he was coming off of an impressive 2010 campaign. However, an injury forced him to miss most of April and his numbers so far have been lackluster. Despite his subpar performance, there are reasons for optimism.

Hart is walking in 10.3 percent of his plate appearances, the highest percentage of his career. He’s also swinging at five percent fewer pitches outside the strike zone than he did last year. With a career high line drive percentage of 20.7 percent, Hart should see an uptick in his batting average in the second half.

Further increasing his value in the second half is the decision of manager Ron Roenicke to make Hart the Brewers new leadoff hitter. Sure the RBI will suffer but the run potential is enormous with Ryan Braun and Prince Fielder hitting behind him. There’s a reason Rickie Weeks is leading the National League in runs scored this year. Hopefully the move atop the lineup will encourage Hart to steal bases once again.

Madison Bumgarner, SP, San Francisco Giants

Let’s play a little game of guess who.

Player 1: 110.2 IP | 3.74 ERA | 1.33 WHIP | 96 K
Player 2: 110.1 IP | 3.11 ERA | 1.25 WHIP | 95 K

Player 1 is Bumgarner and player 2 is Bumgarner if you take out his June 21 stinker against Minnesota where he was tagged for eight runs and only recorded one out. Amazing what one bad start can do to a player’s season totals.

Bumgarner is pitching like an ace so far this year and can be acquired at half the cost. His FIP of 2.46 is third best in baseball among starting pitchers, trailing only the All-Star game starters, Roy Halladay and Jered Weaver. Bumgarner has also improved his strikeout rate from last year by nearly a strikeout per nine inning thanks in large part to more velocity on his fastball and a harder, more crisp slider that he’s throwing more often. A pitcher with Bumgarner’s skills should win more than the mere four games he won in the first half, especially playing for the division leading Giants.

Cory Luebke, SP, San Diego Padres

Since moving from the pen to the rotation in late June, Luebke has been tremendous. In four starts he has a 1.50 ERA and 0.67 WHIP to go along with 26 strikeouts in 24 innings pitched. For the season Luebke has a 2.57 ERA and 2.30 FIP. He’s also striking out nearly 10 batters per nine innings. That strikeout rate should fall down to the seven to eight range as a full time starter as Luebke never posted huge strikeout numbers in the minors but he should continue to post good ratios, especially pitching half his games at PETCO Park. He also carries relief pitcher eligibility so for those of you in points leagues, take note.