Burrell was designated for assignment before the Rays' game against the Mariners and Hank Blalock was selected from Triple-A Durham.
Burrell has struggled at the plate so far this season, and his average fell to .202 following an 0-for-4 performance at the plate Friday night against Seattle. The 34-year-old served primarily as the designated hitter against right-handed pitchers while working in a platoon with Willy Aybar, and he had not been particularly effective in that role, striking out 28 times in 84 at-bats while getting just 17 hits.
Blalock, meanwhile, has put up impressive numbers with the Bulls. He hit .349 in 109 at-bats, racking up five doubles, four home runs and 24 RBIs while recording a .405 on-base percentage and .505 slugging percentage.
"We feel like with Hank's left-handed bat and the positional flexibility, that it fits us better right now," said Andrew Friedman, Rays executive vice president of baseball operations. "The way Willy's come on against left-handed pitching made it a situation for us where we felt like a left-handed bat fit us better going forward.
"Not a primary reason for the move, but it definitely helps as we go into National League parks and the flexibility and the potential for double moves, it just makes us much more flexible and dynamic."
When Burrell signed a two-year contract for $16 million with the Rays in January 2009, the deal appeared to be just what the Rays needed to help out their offense, which had struggled against left-handed pitching. But the move did not produce good results.
In two seasons with the Rays, Burrell hit a combined .218 with 16 home runs and 77 RBIs -- none of his home runs came against left-handed pitching. The 11-year Major League veteran is a career .253 hitter with 267 home runs and 904 RBIs. He spent his first nine seasons with the Phillies after being selected first overall by the Phillies in the 1998 First-Year Player Draft.
Rays manager Joe Maddon could only speculate on what went wrong, first suggesting that the problem could have been as simple as not adjusting to the change from position player to DH.
"I don't know," Maddon said. "The thing about Pat, which I respected so much from the first day, is this guy's worked. He worked very hard. He took a lot of abuse from outside sources. I'm always about effort and work. And this guy did that every day. He was the first guy showing up. He was always in the cage, always working on his defense even though he didn't play out there.
"He was very supportive among his teammates. It was just unfortunate that it did not work out. And I really don't have a good reason except maybe switching positions. Switching leagues took its toll."
Friedman met in person with Burrell on Saturday morning and said Burrell handled the move like a professional. Of note, players in the Rays' clubhouse thought the organization showed a lot of class waiting to make the move until Burrell had accrued his 10 years of Major League service time, which he did Friday night.
Blalock, 29, signed a Minor League deal with the Rays in March, and his contract included an out clause that agent Scott Boras told The St. Petersburg Times on Tuesday he would exercise if Blalock was not called up within a week. Several Major League teams, including the Mariners, had previously expressed interest in Blalock.
Friedman answered, "Not much," when asked how much Boras' comments affected Saturday's move. Friedman said the Rays also considered selecting Dan Johnson, who, like Blalock, has been playing well at Durham.
"We talked in Spring Training about evaluating it at this point and talking through it, and we spent close to a week really talking through it and going through with both Hank and Dan Johnson," Friedman said. "Dan Johnson's done really well. Swinging the bat really well and somebody we really like a lot. But with Hank, the positional flexibility is something that really helped us, especially as we go to interleague."
To date, Blalock has given the Rays insurance against any number of possibilities at the Major League level. Friedman said he would have been surprised had Blalock not hit at Durham.
"He's a professional hitter," Friedman said. "Again, both he and Dan Johnson are off to good starts. They're both good hitters. And so it really came down to how well Hank's playing in the infield right now."
Maddon explained that the move will allow the DH to be moved around more on a nightly basis, giving the team "more of a fluid DH."
"Willy against lefties, Hank against righties, and furthermore if you want to get Carlos [Pena] a day off his feet and have him still DH, you've got Hank over there also," Maddon said. "He gives us all of that. He gives us a little more flexibility in the lineup positionally and in regards to the left-right-handed DH stuff. Also, I believe he's going to fit into our culture well. He's going to fit into the clubhouse well, I got to know him during Spring Training and I like him."
Maddon noted that if Burrell had been hitting the way he once had, no move would have been made on Saturday, "but we had different options and one of them was Hank."
Maddon wanted to see Burrell in person on Saturday, but had to settle for talking to him on the phone. Like Friedman, he complimented Burrell's professionalism and he conceded that he was surprised that things did not work out better with Burrell.
"But who knows what might happen over the next couple of months?" Maddon said. "But listen, I wish him well. And I wish that he gets back to the abilities that he showed in Philadelphia. I just hope that it's in the National league where he shows it.
"Again, I have no solid answers. I wasn't around him before. And based on work ethic and caring, the way he conducted himself. You would think it would have worked out better."
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.