— The Baltimore Orioles arrived here riding the momentum of a three-game sweep of the New York Yankees at Camden Yards. Then they upgraded their starting rotation Tuesday afternoon, adding right-hander Scott Feldman from the Chicago Cubs in a trade that dispatched struggling pitchers Jake Arrieta and Pedro Strop to the Windy City.

But their performance Tuesday night against the reeling Chicago White Sox at U.S. Cellular Field was nothing to write home about.

Starter Jason Hammel unraveled in the late innings as the Orioles dropped a 5-2 decision on Chicago’s South Side to snap their four-game winning streak.

The loss, combined the Boston Red Sox’s 4-1 win over the San Diego Padres, dropped the Orioles (47-37) to 3 ½ games behind division-leading Boston in the American League East standings.

The White Sox entered the night losers of five straight and 13 of their past 17, but they opened up a close game with a three-run seventh inning capped by Adam Dunn’s mammoth two-run homer off Hammel (7-5).

The Orioles managed six hits in seven innings against White Sox left-hander John Danks (2-5), who held the Orioles to two runs and struck out four and walked one.

Brian Roberts’s solo home run in the third inning put the Orioles up 1-0. Hitting from the right side, Roberts took a first-pitch delivery into the left field seats. For Roberts, who was playing in his second game and first at second base since coming off the disabled list, it was his first homer since April 13, 2011.

Roberts also made a nice defensive play in his first game in the field since April 4, charging a ball hit by Alexei Ramirez that took a high hop over the mound, barehanding it on the run and throwing to first to nab the speedy Ramirez in the third inning.

The White Sox (33-47) scored single runs in the fourth and sixth off Hammel before the three-run seventh.

The Orioles answered with a run in the eighth on Adam Jones’s RBI single, but White Sox closer Addison Reed earned his 22nd save with a scoreless ninth.

In the trade with the Cubs, the Orioles made a statement that they are committed to building for a deep playoff run this season, acquiring Feldman along with catcher Steve Clevenger for right-handers Jake Arrieta and Pedro Strop.

The Orioles also sent two international bonus slots, a combined $400,000 to spend on international free agent signings, to the Cubs in the deal.

The key part of the trade is the acquisition of Feldman, who is 7-6 with a 3.46 ERA in 15 starts with the Cubs, and who will bolster an Orioles rotation that had a 4.79 ERA entering Tuesday, ranked 27th of 30 major league teams.

“I think when you have a number of players who are having a good year like we are, you have to address the needs of the ballclub and put your focus on this year’s club,” Orioles Executive Vice President Dan Duquette said. “And this year’s ballclub needs more stable starting pitching, and that’s what this trade is designed to address.”

A free agent at season’s end, Feldman is 46-50 with a 4.66 ERA over nine seasons. He pitched for the Texas Rangers from 2005 through 2012, and went 17-8 with a 4.08 ERA in 34 games (31 starts) in his best season in 2009.

The 30-year-old Feldman, who owns a 3-0 record and 2.49 ERA in seven career games at Camden Yards, has recorded nine quality starts in 15 outings this season and has gone at least six innings in 10 of his last 12 starts.

“He’s a proven veteran starting pitcher and he’s pitched very well in this ballpark,” Duquette said. “He’s pitched in the postseason, he won 17 games once and he is on his way to having a good year this season.”

Clevenger, a Baltimore native, will be optioned to Class AAA Norfolk.

Arrieta was the Orioles’ opening day starter a year ago and won a spot in the rotation this spring. But he was 1-2 with a 7.23 ERA this season and spent the year shuttling between the Orioles and Class AAA.

Strop was an instrumental part of the Orioles’ playoff run in 2012 as the team’s setup man for most of the season, but this season, Strop was 0-3 with a 7.25 ERA, allowing 10 runs in his last nine appearances.

— Baltimore Sun