As of 12:01 am ET Saturday, free agents are free to negotiate and sign with any team. Free agency is underway, but like the regular season, it is a marathon, not a sprint. The major deals are most likely a few weeks away.

To help acquaint you with this winter's free agent class, we will be providing position-by-position breakdowns in the coming days. We begin with the crop of catchers, which, predictably, is rather thin. Quality catching is hard to find, and when teams do find it, they tend to hold onto it. Not many top catchers hit the open market. Here are the 10 best.

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1. Matt Wieters

Wieters is, by far, the best catcher in free agency this offseason despite playing only 101 games from 2014-15 due to Tommy John surgery. That includes 75 total games in 2015: 55 at catcher, 13 at DH and three at first base. The Orioles took it easy on Wieters after he returned from elbow reconstruction, so he started back-to-back days behind the plate only five times this past season.

When healthy, the 29-year-old Wieters hit .249/.315/.434 (102 OPS+) from 2011-13 with three 20-plus home run seasons. He also won a pair of Gold Gloves thanks mostly to his arm. Wieters threw out 37 percent of attempted base-stealers from 2011-13, which is elite; the MLB average was approximately 26 percent those years. Both StatCorner and Baseball Prospectus have rated Wieters as a below-average pitch-framer in recent years.

The elbow injury undoubtedly hurts Wieters' market. Teams haven't seen him at full strength since 2013. Catching is in very high demand though, and while you hate to call a procedure as serious as Tommy John surgery routine, it does have a high success rate. Wieters is a switch-hitter with power and a strong defensive catcher to boot. That's very valuable.

The O's made Wieters the one-year, $15.8 million qualifying offer prior to Friday's deadline, which means if he signs with a new team, they will have to forfeit their top unprotected draft pick to sign him. That will also hurt his market a bit, but again, quality catching is hard to find, and Wieters is easily the best available this offseason.

2. Alex Avila

Avila, 28, has never come close to repeating his 2011 season, when he hit .295/.389/.506 (142 OPS+) with 19 home runs. He's authored a .224/.334/.360 (92 OPS+) batting line since, including .191/.339/.287 (77 OPS+) in 67 games around a knee injury in 2015. His true talent at this point is closer to a 92 OPS+ than a 77 OPS+.

Although the knee injury limited him to only 44 games at catcher this past season -- Avila also played 23 games at first base -- he is a solid catch-and-throw guy. Avila has thrown out 34 percent of would-be base-stealers the last two seasons. The metrics say he is a below-average pitch-framer, however.

It's worth noting Avila has a history of concussions, which is scary for any catcher. Add in the fact he's never hit left-handed pitchers well (career 64 OPS+ vs. LHP) and you have a platoon catcher with some injury red flags.

3. Chris Iannetta

Iannetta is a flawed catcher who can be quite productive at times. He hit only .188/.293/.335 (78 OPS+) with 10 home runs in 92 games this past season, though last year he managed a .252/.373/.392 (123 OPS+) line with seven home runs. In four years with the Angels, Iannetta hit .226/.342/.374 (105 OPS+).

Although he has thrown out only 24 percent of attempted base-stealers over the last three seasons, Iannetta has improved considerably as a pitch-framer, to the point where he is now one of the best in the game. At 32 years old, he's a guy who will take a walk, run into the occasional mistake pitch, and steal a boatload of strikes for his pitching staff.

4. Dioner Navarro

The No. 4 catcher on our list barely caught in 2015: Navarro played only 39 games behind the plate after the Blue Jays signed Russell Martin, though he also missed a month with a hamstring injury. The 31-year-old hit .246/.307/.374 (88 OPS+) with five home runs in 54 games this season.

Navarro, 31, is a below-average defensive catcher according to both the stats and the eye test. His throwing is spotty and the numbers say he costs his team strikes with his pitch-framing. Navarro's value is in his contact-oriented approach -- since resurfacing in 2013, he has a solid 14.4 percent strikeout rate -- from both sides of the plate.

5. Geovany Soto

It has now been seven years since Soto won the NL Rookie of the Year award in 2008 thanks to 23 homers and a 119 OPS+. The soon-to-be 33-year-old split time behind the plate with Tyler Flowers this past season and hit .219/.301/.406 (96 OPS+) with nine home runs in 78 games.

Like most catchers, Soto has a bit of an injury history, limiting him to only 123 starts behind the plate from 2013-15. His arm is strong and his pitch-framing rates well, but it's worth noting Soto has the yips. He has a hard time simply throwing the ball back to the pitcher. His return throws to the pitcher look like this:

Soto drops to his knees and almost shot puts the ball back to the pitcher. He has no trouble throwing to the bases on steal attempts, it's just the routine throw back to the pitcher that gives him trouble. I wonder if teams will look the other way or see that as a sign bigger throwing problems are on the way.

6. Jarrod Saltalamacchia

The Marlins released Salty in the middle of the 2015 season, but he was able to hook on with the Diamondbacks, and he quietly had a nice little year with them. The 30-year-old switch-hitter posted a .251/.332/.474 (115 OPS+) line with eight home runs in 70 games with Arizona. Over the last three seasons he's a .243/.325/.421 (104 OPS+) hitter.

Saltalamacchia has always been a well-below-average defensive catcher, however. He's thrown out only 20 percent of attempted base-stealers the last three years and the various metrics says he's one of the game's worst pitch-framers. Having a switch-hitter with some pop behind the plate is really nice. But Salty is going to give a lot of that back defensively.

7. A.J. Pierzynski

A little more than seven weeks shy of his 38th birthday, Pierzynski is still a workhorse behind the plate and providing value on offense. He started another 104 games at catcher in 2015 -- he's started at least 100 games behind the plate in 14 of the last 15 years -- and hit .330/.339/.430 (114 OPS+) with nine home runs for the Braves.

Pierzynski is a below-average thrower and one of the worst pitch-framers in the game, so his value lies in his bat. Over the last three seasons he's struck out in only 10.3 percent of his plate appearances, so if you're a team looking for a veteran backstop who will put the ball in play, Pierzynski may be your guy. Buyer beware though: Pierzynski is known to be a bit ornery, and at age 38, he could fall off the cliff at any moment.

8. Jeff Mathis

Mathis, 32, is a brutal hitter, putting up a .161/.214/.290 (38 OPS+) line in 2015 and .194/.254/.306 (52 OPS+) line in more than 2,100 career plate appearances. He's also an excellent defensive catcher, throwing out base-stealers at a high clip and framing pitches at an above-average rate. Mathis also has a reputation for being a strong leader and working well with his pitching staff. The offense is just not going to happen, but if you're looking for a quality defensive backup catcher with great intangibles, Mathis is the guy.

9. Brayan Pena

Once upon a time Pena was nicknamed "the Cuban Ichiro" because he puts the ball in play so effortlessly: He had a 9.3 percent strikeout rate in 2015 and 11.0 percent for his career. (The MLB average was 20.4 percent this season.) Pena hit .273/.334/.324 (82 OPS+) in 2015 and .271/.313/.354 (84 OPS+) from 2013-15, so the contact leads to a nice batting average but not much else. Pena, 33, is a below-average defender but has a reputation for being a positive and upbeat clubhouse guy.

10. Carlos Corporan

Corporan, 31, is another defense-first backstop. He hit .178/.244/.299 (46 OPS+) in 33 games with the Rangers this year while dealing with a thumb injury. Corporan is a below-average thrower but a strong pitch-framer, so he'll steal your pitching staff some strikes and not much else. He might be looking at a minor-league contract to serve as someone's third catcher in Triple-A.

Matt Wieters is the best available free agent catcher this offseason.
Matt Wieters is the best available free agent catcher this offseason. (USATSI)