NEW YORK — A talented crop of young pitchers is a source of optimism within the A's organization.

With the trades of starters Rich Harden and Joe Blanton, even more focus will be placed on those young arms.

Greg Smith is counted among that group.

The left-hander was a bright spot during the A's first half, but he stumbled Friday night at Yankee Stadium as the A's opened the second half with a 7-1 loss before a crowd of 54,145.

The defeat was the A's third straight dating back to before the All-Star break, and it represents their first losing streak of more than two games since a four-game skid May 28-31.

For the 11th time in Smith's 19 starts, the A's were held to one run or fewer.

But the rookie hardly was pointing fingers after lasting just 32/3 innings, the shortest outing of his career. He walked five and was tagged for eight hits and six earned runs.

"Walks are going to hurt you (against) anybody, especially with a good-hitting team like they are," Smith (5-8) said. "Falling behind guys and having to put fastballs in the zone was the bottom line."

Originally scheduled to start today, Smith was bumped up after Blanton was traded to the Philadelphia Phillies on Thursday. Smith didn't lean on that for an excuse, nor did he blame his eight-day layoff as a result of the All-Star break.

"There was a little bit of rust. Maybe that was part of it, maybe it wasn't," he said. "I'm not going

Smith's biggest mistake came on a 1-2 cutter in the third inning that Robinson Cano drilled for a three-run homer that put the Yankees on top for good, 4-1.

By that time the A's had mustered all they would scrape together against Mike Mussina (12-6), who allowed nine hits in six innings but just a lone first-inning run.

The A's struck out 12 times against four New York pitchers and didn't put a single runner on base after the fifth.

"We (didn't) take advantage of some opportunities," said shortstop Bobby Crosby, who went 1-for-4 in his return from the disabled list. "(Mussina) started hitting his spots and using his two-seamer really well."

The Yankees, trying to spark an inconsistent offense themselves, signed first baseman Richie Sexson and thrust him into the lineup (headline from Friday's New York Daily News: "Yankees bring Sex to the city").

Sexson was released by Seattle last week after a season long slump, but he was hitting .344 against lefties. He continued that hot trend against Smith, lining an RBI single in his first at-bat in pinstripes to tie the game in the bottom of the first.

Alex Rodriguez went 3-for-4 with two RBI, including an opposite-field solo shot off Dallas Braden in the sixth.

Braden's one inning was noteworthy after A's manager Bob Geren announced before the game that Braden would start Tuesday at Tampa Bay, filling the hole in the rotation left by Blanton.

Left-hander Lenny DiNardo was called up from Triple-A Sacramento to take Blanton's roster spot and will work out of the bullpen.

Choosing Braden is a mild surprise, considering the left-hander had made just one appearance before Friday since being recalled from Sacramento on July 8.

But he had impressed over his previous five starts with the River Cats, including 18 strikeouts and no walks in his final two starts.

"Dallas was pitching very well down there," said Geren, who didn't commit on his plans for Braden past Tuesday's start.

The decision, for now, ends speculation on whether hot prospect Gio Gonzalez would be called up from Triple-A.

Contact Joe Stiglich at jstiglic@bayareanewsgroup.com.