Each player cost the team $50,000, and all three must remain on the Padres' 25-man roster the entire season or be offered back to their original team for $25,000.
The Padres had good luck with the Rule 5 Draft last year as pitcher Kevin Cameron had a 2.79 ERA in 48 games, and he factors into their future bullpen plans.
The Padres think just as much, if not more, about Guevara.
"He's got a great screwball, a great strikeout-to-walk ratio and is a guy who has nailed it at about every level," Padres general manager Kevin Towers said of the 25-year-old who was 1-2 with a 2.32 ERA for Double-A Chattanooga last season, with 87 strikeouts in 62 innings.
Guevara was the Reds' seventh-round pick in 2003 and averaged 12.63 strikeouts per nine innings, with only 23 walks in 62 innings.
"He was our No. 1 guy," Towers said. "We were trying to get the No. 1 pick to get him."
Gardner, 26, is a right-hander who was 3-5 with a 2.88 ERA in 44 games for Double-A Trenton, a Yankees affiliate. Towers said he's "in the mix for the bullpen."
The Padres like Crabbe because of his versatility, as he can not only play second base but everywhere else in the infield (but first base) and outfield, as well. He also has something few players on the roster have: speed.
"He's a super-utility guy," Towers said. "He's a better-than-average defender at the middle-infield positions and has speed."
Crabbe, 24, hit .287 with nine home runs, 38 RBIs and 17 stolen bases for the Brewers' Triple-A team in, oddly enough, Nashville, where the Winter Meetings were held.
Crabbe could push rookie Matt Antonelli for the team's starting second base job, though he might be a better fit in a utility role for the Padres.
The Padres lost two players Thursday in the Triple-A phase of the draft, though neither were considered top prospects.
The Giants selected shortstop Juan Ciriaco, who played at Class A Lake Elsinore, and the Orioles picked first baseman Tim Brown, who played for Double-A San Antonio in 2007.