MIAMI -- After finishing last in the Major Leagues in home runs and second to last in runs scored last season, the Marlins on Monday made a series of moves that promise to dramatically upgrade their sluggish offense.

Minutes after the 8 p.m. ET tender deadline, the Marlins announced they had acquired infielder Jonathan Villar in a trade with the Orioles and claimed first baseman Jesús Aguilar off waivers from the Rays.

For Villar, who was designated for assignment on Wednesday, Miami dealt left-handed pitching prospect Easton Lucas.

To make room on the Marlins' 40-man roster, infielder JT Riddle and Tayron Guerrero were designated for assignment. Riddle, who was arbitration-eligible, has also been non-tendered, meaning he is a free agent.

Additionally, right-hander José Ureña and lefty reliever Adam Conley were each tendered contracts for 2020. Aguilar and Villar also are in the arbitration process with the Marlins. All their contracts will be decided at a later date.

Villar is coming off an impressive season, batting .274 with 24 home runs and 73 RBIs in 162 games. A switch-hitter, he also posted 40 stolen bases and scored 111 runs. The 28-year-old gives the Marlins a legitimate leadoff candidate. He can play second base and shortstop.

A native of the Dominican Republic, Villar broke in with the Astros in 2013, and has hit .261 with a .328 on-base percentage in seven MLB seasons. He's scored 381 runs and stolen 202 bases in 779 games.

Tampa Bay designated Aguilar for assignment on Friday, clearing roster space ahead of Monday night’s non-tender deadline. Now he heads to Miami, where he could be an option at first base.

The Marlins used a combination of Garrett Cooper, Neil Walker and Martin Prado at first base last year, but Walker and Prado are free agents. Cooper (.791 OPS in 2019) is set to return, but he is also an option in the outfield corners. Austin Dean also could be an option at first base this season.

An All-Star with the Brewers in 2018, Aguilar split time between Milwaukee and Tampa Bay in 2019, combining for a slash line of .236/.325/.389 with 12 home runs and 50 RBIs.

Aguilar had a big 2018 with Milwaukee, hitting .274/.352/.539 with 35 home runs and 108 RBIs. He was dealt to the Rays for right-hander Jake Faria at the July 31 Trade Deadline.

A native of Venezuela, Aguilar broke in with the Indians in 2014. In six big league seasons, he has a .256 batting average with 63 home runs and 215 RBIs.

The Marlins hit just 146 home runs in 2019.

Ureña was Miami’s Opening Day starter the past two seasons, but he finished 2019 in the bullpen. The 28-year-old has the flexibility to serve in the rotation or the bullpen.

If the Marlins don’t feel Ureña fits into their 2020 plans, he could be traded before Opening Day.

Entering his second year of arbitration eligibility, Ureña made $3.2 million in 2019, an injury-plagued year in which he finished 4-10 with a 5.21 ERA in 24 games, with 13 starts. He is under club control through the 2022 season.

Ureña went on the injured list with a lower back strain a few days after his three-inning start against the Braves on June 7. He was later diagnosed with a herniated disk.

He returned as a reliever in September and was given chances to close, but that didn’t go well. In 10 innings of relief, he was 0-3 with a 9.00 ERA, compared to 4-7 with a 4.70 ERA in his 13 starts.

Conley, 29, had a rough 2019 season, going 2-11 with a 6.53 ERA in 60 games. The left-hander, in his first year of arbitration eligibility, made $1.125 million in 2019. He’s scheduled to be eligible for free agency after the 2023 season.

The Marlins had high hopes for Conley, but he never got on track. Early in the year, he was part of a late-inning rotation, and even had two saves. But he faltered as the season progressed and was used more in earlier innings and assumed more of a long-relief role.

In 60 2/3 innings, he had 53 strikeouts, 29 walks and a WHIP of 1.73.

Riddle, 28, was eligible for arbitration for the first time, and he made $560,000 in 2019. But he had an injury-plagued year and hit .182 with six home runs in 51 games.

Guerrero had a 6.26 ERA in 52 games and 46 innings.