"This is a guy with a great resume: All-Star Games, Gold Gloves, a playoff team in Arizona -- he was a big part of that team. He's been on other playoff teams," Padres general manager Josh Byrnes said. "Performance wasn't what we needed, and we wanted to give these other guys a chance."
The Padres owe Hudson, 34, an estimated $6.25 million, which includes the rest of $5.5 million this season in addition to a $2 million buyout.
He signed a two-year, $11.5 million contract as a free agent in December 2010. Hudson's deal was done by former Padres general manager Jed Hoyer.
Byrnes and Padres manager Bud Black met with Hudson on Thursday morning.
"Those are always tough. There's no doubt about it," Black said. "It's the worst part of our job, these type of conversations. He was a pro. He understood where this organization is going and understood the hard, cruel business aspect of it."
The Padres placed Bartlett on the 15-day disabled list, retroactive to Tuesday, for a strained right knee. The injury has been ongoing and involves cartilage, Byrnes said. Bartlett is hitting .133 with four RBIs and 27 strikeouts in 29 games.
Bartlett said he and the Padres discussed surgery, but the doctors said he didn't need it. He said he plans to rest the knee through at least the weekend.
"This is something that came about last year," he said. "We did some stuff in Spring Training to help it out. It's just something I'm probably going to have for the rest of my career."
Said Byrnes: "He hasn't played well and probably hasn't moved as well as he normally does. It just seemed like it was a contributing factor.
"Jason understands he goes on the DL, these guys are coming up, and there's no guarantee of a job waiting on the other side. That's just the way we're set up right now."
Cabrera, a switch-hitter, was hitting .333 in 34 games with Tucson. He was 15 for 15 in stolen-base attempts. He made his Major League debut with the Padres in 2009 and has hit .236 in 181 Major League games.
"I think he's smoothed some things out," Black said. "He's worked a lot on all facets of his game. We'll see at this level if there's a difference in him. We'll let this play out over time.
"In Spring Training, we saw a guy that looked more comfortable in the field. He wasn't trying to make things happen defensively. He was letting the game come to him defensively. Offensively, even though the average didn't show it, he had better overall at-bats. That carried over to his season."
Amarista, a left-handed hitter, batted .278 in 29 games between Tucson and Triple-A Salt Lake this season. The Padres acquired Amarista and right-handed pitcher Donn Roach from the Angels in exchange for right-handed reliever Ernesto Frieri on May 3.
Amarista made his Major League debut with the Angels last season and has hit .154 in 24 Major League games. He made the Angels' 2012 Opening Day roster, appearing in one game as a pinch-runner before he was optioned to Triple-A.
Black said Angels manager Mike Scioscia told him he didn't hesitate to play Amarista at shortstop, third base or in the outfield.
"We feel good about him defensively," Black said. "He swings the bat, doesn't strike out, doesn't walk a lot. He puts the bat on the ball."
Adding to the Padres' depth at middle infield, infielder Logan Forsythe is rehabbing with Tucson and second baseman/third baseman Jedd Gyorko was promoted to Tucson from Double-A San Antonio. Forsythe is on the 60-day DL, retroactive to March 26, with a left foot injury.
Forsythe has played third base at Tucson but is expected to get time at shortstop.
"As banged up as we've been, we're starting to create some options and some competition, which is what we set out for at the beginning," Byrnes said.