Here's a quick look back at the key MLB transactions that have taken place over the past week.

Rockies acquire Tyler Chatwood for Chris Iannetta; Sign Ramon Hernandez to two-year, $6.5 million deal

Chatwood was pushed to the big leagues at age 21 with all of 17 starts above High-A in his professional career. That development arc seldom leads to immediate success, but keep in mind that since 1990, only 19 pitchers have tossed 140 or more innings in a big league season at that age.

Chatwood matched Brad Penny for the lowest swinging strike percentage among starting pitchers last season (4.6|PERCENT|), but considering the aforementioned lack of refinement against competition at the higher minor league levels, that shouldn't come as a huge surprise. The Rockies have developing talent behind the plate in the form of Wilin Rosario, but they quickly signed Hernandez to provide a veteran option to ease his transition to the starting role over the next two seasons. While Hernandez hit .282/.341/.446 with 12 homers for the Reds in just 298 at-bats last season, his HR/FB mark spiked to 16.0|PERCENT| after previous marks of 6.2|PERCENT| and 9.2|PERCENT| in 2009 and 2010, respectively. Unless he's counted on for more playing time that he's seen in each of the last three seasons, a double-digit homer repeat is unlikely even in Colorado.

From the Rockies' standpoint, more important than anything Chatwood did on the mound in 2011 is the fact that they have him under club control for five years and he will be just 22 years old this season. Iannetta was locked in for 2012 at a reasonable $3.55 million, but had a $5 million club option with a $250,000 buyout for 2013. Remember, most talented pitchers Chatwood's age spend their age-21 season at High-A or Double-A, taking a tour of the California or Texas League and playing a lot of Call of Duty. To say the Rockies did well in this trade would be an understatement.

Iannetta moves from Coors Field and Angels Stadium, going from an extreme hitter-friendly environment for right-handed hitters to a neutral one. Scott Pianowski also made a strong point on the staff message board suggesting that Iannetta's walk rate will almost certainly drop now that he's no longer hitting in front of pitchers in the National League. His contact rate has stabilized at 74 percent over the last three seasons and while a 17 percent walk rate is almost uncertainly going to drop toward the 10-12 percent range, he's still a significant offensive upgrade over the Mathis, Wilson, Conger trio for the Halos.

Cubs sign David DeJesus for two years, $10 million

For a solid left-handed contact hitter with the ability to play all three outfield positions, the Cubs did well in this contract. He's expected to slot in as the team's everyday right fielder, and the fantasy value here may hinge on where new manager Dale Sveum puts him in the batting order. The contract is moveable if the Cubs aren't competing in 2012 or 2013 and a contender is looking for a veteran outfielder, and it's a far cry from some of the back-breaking deals inked by the previous front office regime. Both of DeJesus' previous home parks suppress left-handed power, but that's not really his game anyway and his career home-road splits don't suggest a significant home-run surge now that half of his games will be played at Wrigley Field. DeJesus turns 32 later this month, but he should be able to provide a pair of seasons in the 2.0-2.5 WAR range.

Royals sign Jonathan Broxton for one year, $4 million

The Royals have flirted with the idea of moving Joakim Soria to the rotation in the past, but that doesn't appear to be the immediate plan following the addition of Broxton. A significant decline in velocity for the second straight season was accompanied by lost control and a general pounding in 14 appearances with the Dodgers in 2011. Fortunately, Broxton had surgery to remove a bone spur and loose bodies from his elbow, so perhaps the root cause of his struggles has been addressed. If Broxton regains his pre-second-half 2010 form, the Royals' bullpen could be lights out in the final three innings with Broxton and Greg Holland forming the bridge to Soria. With Broxton's signing, the Royals have announced that Aaron Crow will be stretched out and given a look as a starting pitcher again this spring.

Rays sign Jose Molina to a one year, $1.5 million deal

If you haven't seen it before, there's an outstanding piece from Mike Fast (@fastballs) https://bit.ly/rPX2Wu at Baseball Prospectus looking at value in catchers' ability to frame pitches. Molina doesn't hit, but the Rays must see Molina's defensive skills (which have been praised for years and go well beyond his ability to earn extra strike calls for his pitchers as Fast's article suggests) similar to the way they viewed Casey Kotchman's defense at first base prior to last season. Keep an eye on which pitcher(s) if any, are given Molina as their personal caddy this year. They should benefit in a way that pays off for your roster.

Rays trade John Jaso to Mariners for Josh Lueke and a PTBNL or cash

Jaso's strikeout rate spiked and his walk rate plummeted in 2011 and given that the Rays signed Jose Molina the day after dealing Jaso to the Mariners, it seems clear that an emphasis on defense is being placed behind the plate in Tampa Bay. From the Mariners' perspective, they're getting four years of control (albeit, three of arbitration) with a catcher who possesses slightly above average on-base skills, and slight below average defense. They're on the hook for another year of Miguel Olivo, so it's likely that the left-handed hitting Jaso gets a crack at the larger share of a platoon behind the plate. Keep in mind the left-handed hitters are much better off at Safeco than righties, so the change in home parks is negligible for Jaso going west from Tropicana Field.

Without thoroughly re-hashing Lueke's past, he's joining his third organization in three years just prior to his 27th birthday despite a career 10.7 K/9IP and 2.3 BB/9IP in the minors and arsenal of three pitches including a mid-90s fastball, slider and splitter. Even in his taste of the big leagues, Lueke carried an 8.0 K/9IP and 3.6 BB/9IP, but was the owner of a dismal (and unlucky) 56.6|PERCENT| LOB rate. Truth be told, Lueke might be a closer at some point down the road and from a baseball skills standpoint and contractual control standpoint (five years), Andrew Friedman and the Rays appear to have quietly made a nice deal here.

Blue Jays acquire Luis Valbuena from the Indians for cash

I'm a firm believer that you don't win friends with salad. I'm also patient (or stubborn, depending on how you look at it) when it comes to player development. Valbuena is now 26 and while his time may be running out in terms of becoming an everyday player at the big league level, I still believe there's talent here as evidenced by his .304/.387/.468 line over 931 career PA at Triple-A. Keep an eye on the Jays' other moves to address second base, as that will ultimately determine what type of role Valbuena will have the opportunity to compete for in 2012.

Dodgers sign Adam Kennedy

The soon-to-be 36-year-old Kennedy will join his fifth team in as many seasons after getting a one-year, $800,000 deal with the Dodgers. Most of his playing time in 2012 figures to come at second and third base, after the Mariners deployed him 36 times at first and 17 times as a DH in 2011 (seriously, we can't hold that against him). Unfortunately, the walk (5|PERCENT|) and contact rates (82|PERCENT|) bottomed out last season and there may not be much in the tank given his age. Look for him to start no more than once or twice each week while giving manager Don Mattingly a left-handed bat off the bench.

Tigers sign Ramon Santiago

Before the addition of Clint Barmes, the Pirates were believed to be interested in Santiago as their everyday shortstop. With the return to Detroit, the light-hitting middle-infielder will remains the team's primary backup to Jhonny Peralta and short while battling Ryan Raburn for at-bats at second base barring another free-agent signing or trade to shore up the keystone.