The AL starting lineup featured three Orioles for the first time since 1997, when Cal Ripken Jr., Roberto Alomar and Brady Anderson all started for the AL.
In AL manager Jim Leyland's lineup, first baseman Davis hit cleanup, center fielder Jones batted seventh and shortstop Hardy was in the ninth spot. Third baseman Machado and pitcher Chris Tillman also made the All-Star team.
Davis and Jones succumbed to Mets rookie Matt Harvey's magic in their first at-bats; Davis flew out to center on an 89-mph changeup in the first inning, while Jones struck out on a 98-mph four-seamer in the second.
"I don't mind facing Harvey one at bat and then having him come out of the game," Davis said. "The guy's got electric stuff. Obviously he has a power arm and the Mets have a guy they can count on for a long time."
In his first at-bat, Hardy lined out to center on an 88-mph slider from Dodgers ace Clayton Kershaw for the first out of the third.
In the fourth, with the Tigers' Miguel Cabrera on second base, Davis ripped a slider from D-backs lefty Patrick Corbin to right field -- off the glove of Reds first baseman Joey Votto -- for a base hit. Cabrera advanced to third on the play, then scored on Blue Jays slugger Jose Bautista's sacrifice fly to center to give the AL a 1-0 lead.
Jones led off the fifth with a double, lining a 2-2 cutter from Phillies lefty Cliff Lee to left. Jones advanced to third on a single by Minnesota's Joe Mauer, then scored on a ground ball by Hardy to give the AL a 2-0 lead.
Davis got a third and final at-bat in the sixth, striking out on an 84-mph curveball by Marlins rookie Jose Fernandez.
Davis was replaced in the sixth by the Tigers' Prince Fielder. Davis went 1-for-3 with a strikeout and left two runners on base.
Machado also entered in the sixth, replacing Cabrera at third.
In the seventh, Machado robbed the D-backs' Paul Goldschmidt of a hit with a sparkling backhanded grab on a sharply hit one-hopper down the third-base line. He turned and threw across his body to nail Goldschmidt at first.
Jones got his third and final at-bat in the seventh, facing Reds reliever Aroldis Chapman. He struck out swinging on a 101-mph four-seam fastball. Jones was replaced by the Royals' Alex Gordon, who went to left field, moving the Angels' Mike Trout to center. At the same time, Hardy was replaced by Tigers shortstop Jhonny Peralta.
Davis, Jones and Hardy were all voted as starters by the fans, with Davis, the Major League's home run leader, coming in as the top vote-getter. Machado was selected as an AL reserve and Tillman was named to the team on Sunday in place of Tigers pitcher Justin Verlander, who was unavailable to pitch after starting Sunday in Detroit.
Davis set an AL record with 37 home runs before the All-Star break and is second in the Majors with 93 RBIs. The 27-year-old slugger also participated in the Chevrolet Home Run Derby on Monday night, reaching the second round.
Davis opened a blister on his hand midway through the Derby and had his palm bandaged for the game, but he suffered no ill effects.
"The skin came off a little bit," Davis said. "It wasn't going to stop me; I didn't come here to sit the bench."
Jones, 27, finished the first half with a .296 batting average, 19 home runs and 67 RBIs. The two-time Gold Glove Award winner also appeared in the '09 and '12 All-Star Games, and was named Most Valuable Oriole in '11 and '12.
Hardy, 30, is a defensive stalwart who won a Gold Glove last season, but is also the only shortstop to hit more than 20 home runs in the last two years. He has already hit 16 homers in 2013.
Hardy was feeling the pressure of the packed All-Star schedule.
"With all the interviews and the signings, there's really not much time to prep," he said before the game. "It's maybe stressing me out a little bit, but once the game starts, I will be fine, when it's all about the baseball."
Machado, one of the league's top young players, turned 21 earlier this month. He hit 38 doubles before July 1, the second-most in the Majors since 1921, and had a career-high 14-game hitting streak earlier this season. He ranks second in the AL with 128 hits and 11th with a .310 batting average.
Tillman, 25, leads the Orioles with 11 wins and has a 3.95 ERA in 19 starts this season. He has 89 strikeouts in 111 2/3 innings, but did not appear in Tuesday's game.