The Phillies released O'Sullivan after the season. McGuinness earned 34 at-bats with Texas in 2013, but did not play at the major league level last year. Slowey was released by Miami in June after a poor performance.
Villanola has yet to earn an at-bat in the major leagues.
Prado hit .282 with 12 homers and 58 RBI in 143 games played between the Yankees and Diamondbacks. Phelps went 5-5 with a 4.38 ERA and 92 strikeouts over 113 innings pitched.
Eovaldi registered a 4.37 ERA, a 1.33 WHIP and 142:43 K:BB ratio over 199 2/3 innings as a starter in Miami. Jones hit .246 with 15 homers and 53 RBI over 496 at-bats in his lone season with the Marlins.
Morse played a crucial part in San Francisco's championship run in 2014, batting .279 with 16 home runs, 32 doubles and 61 RBI in 131 regular season games. He had just six hits over 20 postseason at-bats.
Morse heads to Miami with a .281/.335/.473/.808 slash line over 10 seasons in the majors. He helped San Francisco to a World Series title in 2014, while batting .279 with a .475 slugging percentage, 16 home runs, 32 doubles and 61 RBI in 131 regular season games.
In nine career games at Marlins Park, Morse has a .314 average, .457 slugging percentage, .771 OPS, one triple, three doubles and five RBI.
According to CBSSports.com Baseball Insider Jon Heyman, the Orioles are one of eight teams on Howard's pre-approved list for trades. An American League team seems like an ideal landing spot for the veteran, who could spend the final two years of his contract as a designated hitter. However, according to Heyman, there's "not a lot there at the moment" between the two clubs.
Howard has two years and a guaranteed $60 million remaining on his contract, with a $23 million option for 2017. He slashed .223/.310/.380 with 23 homers, 95 RBI while also striking out 190 times over 569 at-bats last season
Mayberry has a .241 average, .305 on-base percentage, .429 slugging percentage and .734 OPS in six MLB seasons. He also has 53 career home runs.
Mayberry has a .208 average, two home runs, five doubles and 12 RBI in 31 career games at Citi Field.