Health will be the biggest question for both. On Friday, after the Mariners finalized their one-year deal with Hart and the trade with Miami to acquire Morrison, they both said they were ready for a full season after knee troubles in the past.
Seattle capped a hectic two days of activity after both players passed physicals on Friday. Morrison was acquired for right-handed reliever Carter Capps from the Marlins, while Hart signed an incentive-laden $6 million, one-year deal that could be worth up to $10.65 million if he's healthy and has 650 plate appearances.
The moves came a day after Seattle's big splash when it completed the $240 million, 10-year deal with free agent second baseman Robinson Cano.
"You look at the ball clubs and you want to go to a place that's kind of headed in the right direction and with them signing (Cano) I saw the organization is definitely moving forward," Hart said.
Hart's decision to come to Seattle was partly due to a longstanding relationship with Mariners general manager Jack Zduriencik, who was part of the Milwaukee front office that draft Hart. That familiarity helped seal Hart's decision, as did little factors like spring training in Arizona and the opportunity to give his body a rest but stay in the lineup being used as a designated hitter.
The ability to get a break occasionally and still DH was important for both players.
"It does give you some versatility. For both players now being in the American League where we have the DH is going to help both guys," Zduriencik said. "Between right field, first base, designated hitter and a chance to get them off the field a little bit and get a break is going to help both guys.
If Hart can stay healthy, getting the two-time All-Star for one season on a relatively inexpensive deal could be a significant coup for the Mariners, who have made adding offense a top priority this offseason. It started with Cano's deal continued by adding a needed right-handed bat in Hart that can provide protection in the lineup.
Hart did not play in 2013 because of a right knee surgery in January 2013 after a meniscus tear and joint damage was discovered. It was his second knee surgery in a year after having his right knee operated on before the start of the 2012 season to repair damaged cartilage.
His last season in 2012 was one of the best in his career. Hart hit .270 with 30 homers and 83 RBIs with Milwaukee. Hart also had 35 doubles in 2012 and posted an on-base plus slugging percentage of above .800 from 2010 through 2012.
Hart was cleared for full activity about two weeks ago, he said, but had been working out at nearly full capacity for about six weeks. He's lost weight and feels he could play in the outfield about five days a week without issue. Seattle sent scouts to watch Hart's workouts in Arizona before making the offer.
Morrison also fits Seattle's need of having the versatility to play a few different positions and be an option at first base. He has not been able to match the power he showed during the 2011 season when he slugged 23 homers and had 72 RBIs for the Marlins, slowed by injuries. He had right knee surgery in September 2012 and missed the first two months of the 2013 season. He played 85 games last season for Miami and nearly all of them at first base in the field.
"We really haven't seen a productive LoMo since the 2011 season. There's still a ton of potential there with LoMo," Marlins president of baseball operations Mike Hill said.
Morrison said it's been two seasons since he had a full spring training and expects that's where the position decisions will be figured out. He also showed off a bit of his personality that has drawn him more than 100,000 Twitter followers, joking about being willing to play center field if needed and having to do workouts rehabbing that were more for older people than a 26-year-old baseball player.
"I'm so excited to be here now and getting a fresh lease on my baseball life, it's a pretty cool feeling," Morrison said. "I wish the season started now."