Rentals such as Mike Morse, Kendrys Morales, Matt Garza, Scott Feldman, Ricky Nolasco, Edinson Volquez, and Frank Francisco figure to have their names kicked around the trade market this summer, assuming decent performance from the players and a lack of playoff potential from their employers.  More appealing, however, are players who are under team control beyond this year.  Names to watch:

• David Price, Rays.  Price owns a 6.25 ERA on the season, but his struggles with the longball and hits allowed shouldn't last.  However, his average fastball velocity is at a career-worst 93.3 miles per hour.  The Rays remain a legitimate contender, but if they fall back over the next few months and Price's numbers stabilize, there will be a feeding frenzy.  He's under team control through 2015, though only a few select teams could assemble the necessary package of premium young talent.
• Chase Headley, Padres.  The Padres have talked about making a franchise-record offer to retain Headley, which doesn't mean much since their biggest contract was worth $52MM.  If Headley sticks to his word of not negotiating during the season, the Padres must choose between trading him this summer at peak value, or being forced to deal him during the offseason if talks break down.  The Padres could also look to move controllable players such as Carlos Quentin, Huston Street, Luke Gregerson, and Nick Hundley.
• Giancarlo Stanton, Marlins.  The young slugger is under control through 2016.  He's currently on the DL with a hamstring strain, and the Marlins probably won't want to sell low on the biggest trade chip this summer.  The Marlins may weigh trading Kevin Slowey (under control through next year) or Steve Cishek (through 2017).
• Josh Willingham, Twins.  The Twins are only a game under .500, but if they fall out contention, Willingham could command a premium since he is signed affordably through 2014.  The Twins also have appealing, under-contract relievers in Glen Perkins and Jared Burton.
• Andre Ethier, Dodgers.  The Dodgers could look to unload Ethier's contract, which pays $52MM over 2014-17.
• Jake Peavy, White Sox.  Assuming Peavy's back spasms turn out to be a minor issue, the Sox could market him as something close to an ace.  He's signed through next year but can trigger a player option for 2015 by meeting certain criteria.  Alex Rios and Matt Thornton could be popular as well.
• Tommy Hanson, Angels.  If the Angels aren't contending and feel they might non-tender Hanson after the season, a trade makes sense.  Same goes for the Brewers' John Axford and the Padres' Clayton Richard.
• Bud Norris, Lucas Harrell, Wesley Wright, Justin Maxwell, Chris Carter, Astros.  No one seems off-limits on the Astros, though Jose Altuve would be extremely difficult to pry loose.  Norris is under team control through 2015, Harrell through '17.
• Cliff Lee, Phillies.  Lee is under contract through 2015, with a pricey club/vesting option for '16.  He can block trades to 21 teams each season.  If the Phillies decide to blow up the roster, getting a deal similar to Boston's purge of Adrian Gonzalez, Carl Crawford, and Josh Beckett could work.  Lee could serve as the Gonzalez piece, with Ryan Howard tacked on to fill the Crawford role.
• Ike Davis and Jon Niese, Mets.  I generally considered these two as building blocks for the Mets before this season, but if they're playing acceptably this summer I wonder if the team might be willing to discuss them.  Daniel Murphy and Bobby Parnell would hold appeal to other teams as well.
• Alfonso Soriano and David DeJesus, Cubs.  Owing Soriano $18MM for 2014 is generally not viewed as a plus, but he is technically controllable.  With a $6.5MM club option for '14, DeJesus is more appealing.  The Cubs could shop Carlos Villanueva, Scott Hairston, and Nate Schierholtz as well.  It's also worth noting that team ace Jeff Samardzija is under control only through 2015, so if the team can't lock him up and things look bleak for '14, they should entertain offers.
• The Blue Jays are 11-21 on the season and appear likely to become deadline sellers.  While controllable players such as Brandon Morrow and Colby Rasmus would draw interest, it seems more likely to me that the Jays will re-tool and make another push for 2014.  If so, dealing controllable players might not make sense.  I feel similarly about the Brewers.
• The most commonly traded controllable players are, of course, prospects.  We may see names like Jurickson Profar and Mike Olt (Rangers), Nick Castellanos (Tigers), Gregory Polanco (Pirates), Matt Davidson (Diamondbacks), and any number of Cardinals arms bandied about in the coming months.

Catcher Brian McCann will join the Braves tonight in Cincinnati to make his season debut against the Reds.  The 29-year-old missed the first month and change of the 2013 season following August shoulder surgery last year.  It's a big year for McCann, who will be eligible for free agency after the season.  Six other impending free agents project to make their season debuts this month: Corey Hart, Matt Garza, Curtis Granderson, Colby Lewis, Francisco Liriano, and Frank Francisco.  After beginning with all that positive news, here's a look at 2014 free agents currently on the shelf:

• Roy Halladay is likely to hit the DL for a shoulder ailment that dates back to April 24th, which he says is different from last year's malady.  The Phillies' righty will fly to Los Angeles this week to be examined by Dr. Lewis Yocum.  Halladay, 36 this month, has an 8.65 ERA in 34 1/3 innings and seems likely to sign a one-year deal in the offseason.
• The Blue Jays' Josh Johnson is on the DL with triceps soreness, and we haven't heard anything about his timetable.  JJ is headed further downward on our 2014 Free Agents Power Rankings, while Halladay is out of the top ten.
• White Sox righty Gavin Floyd has an appointment this morning with orthopedic surgeon David Altcheck, notes Daryl Van Schouwen of the Chicago Sun-Times.  Tommy John surgery is a strong possibility for Floyd, who would then project to miss at least the first month of the 2014 season under his new contract.
• Speaking of free agents signed coming off Tommy John surgery, the Cubs' Scott Baker resumed his throwing program a week ago.  Baker has had some setbacks after the April 2012 procedure.
• Oakland's Coco Crisp had an amazing start to the season, but hasn't played 140 games in a season since '07.  He's on the DL with a strained hamstring.  That's the same injury affecting Baltimore's Brian Roberts.
• Aside from Granderson, the Yankees have future free agents Derek Jeter, Kevin Youkilis, and Joba Chamberlain on the DL.  Jeter, who fractured his ankle last year, will not reveal his target date for his season debut, but the team expects him out until after the All-Star break.  Jeter will face a $9.5MM player option after the season with a $3MM buyout.  Youkilis has a lumbar spine strain, while Chamberlain strained his right oblique.
• The Mets' Johan Santana is out for the season with shoulder surgery, while the Cardinals can't count on Rafael Furcal (Tommy John) or Chris Carpenter (thoracic outlet syndrome) this year.  The Orioles' Tsuyoshi Wada signed a two-year, $8.14MM deal in December 2011, but had Tommy John surgery in May 2012 and has yet to make his big league debut. 
• Dodgers starters Chris Capuano (strained left calf) and Ted Lilly (strained rib cage muscle) both reside on the DL, at a time when they actually had an opportunity to be in the rotation. 
• The Indians' Brett Myers is weeks away from a return to action after suffering elbow inflammation.  Oakland's Chris Young is battling a strained left quad, while the Tigers' Octavio Dotel has elbow inflammation.

Last offseason, the hardest-throwing free agent based on 2012 velocity data from FanGraphs was reliever Brandon League.  With an average fastball velocity of 95.2 miles per hour, League signed what most considered an above-market three-year, $22.5MM deal with the Dodgers that also has a vesting option for 2016 based on games finished.  League was followed by free agent relievers Matt Lindstrom (94.8), Jonathan Broxton (94.7), and Mark Lowe (93.9).  As you might expect, flame-throwing free agent starters were harder to come by.  Edwin Jackson (93.5), Francisco Liriano (93.0), and Jeremy Guthrie (92.8) led that group.  Which 2014 free agents can boast of the best velocity so far this season?

Relievers

1. Joel Hanrahan – 96.9
2. Fernando Rodney – 95.6
3. Matt Lindstrom – 94.5 (club option)
4. Jesse Crain – 94.3
5. Joba Chamberlain – 94.0
6. Matt Thornton – 93.8 (club option)
7. Boone Logan – 93.3
8. Matt Albers – 93.1
9. Grant Balfour – 93.0
10. Jose Valverde – 92.9

Starters

    1.  Josh Johnson – 92.6
    2.  A.J. Burnett – 92.4
    3.  Jason Hammel and Edinson Volquez – 92.3
    5.  Phil Hughes – 92.0
    6.  Ervin Santana – 91.7
    7.  Gavin Floyd – 91.5
    8.  Mike Pelfrey – 91.3
    9.  Scott Kazmir – 91.2
  10.  Ubaldo Jimenez – 91.2

Average velocity for all qualified starting pitchers this year is 90.4 miles per hour, exactly what you'll find from 2014 free agent Hiroki Kuroda.