Rangers 7, Nationals 4

The back-to-back wild pitches already had Frank Robinson leaning against the railing in the visitors dugout at Ameriquest Field, pursing his lips in disgust, bowing his head to escape the gaze of the sellout crowd of 48,663. The bouncing balls had followed three home runs from the slugging Texas Rangers, yet Robinson, the Washington Nationals' manager, stared straight ahead. No one warmed up in the Washington Nationals' bullpen.

When Tony Armas Jr. unleashed his next pitch, Texas's Mark Teixeira tore into it, lining it over the left field wall for his second homer in as many at-bats, a touchdown-sized lead for the Rangers, and the continuation of a lethargic series for the Nationals, who lost 7-4.

Worse, the inactivity in the bullpen signaled something more. Robinson, who has been quick to yank pitchers for much of the season, was hamstrung Saturday night, limited by injuries that will thrust his long reliever -- Sun Woo Kim -- into a starting role in Sunday's series finale, replacing Esteban Loaiza, who is out with a sore neck.

"I couldn't go to the bullpen in the second inning, first inning," Robinson said. "I only had four guys out there."

So Armas (3-4) was left to absorb the punishment, and after getting pummeled, he settled down enough to save outright embarrassment for the Nationals, who still lead the National League East, even if they haven't looked like it the past two nights. After giving up the four homers -- two from Teixeira, one apiece from Alfonso Soriano and Gary Matthews Jr. -- Armas managed to throw three scoreless innings, salvaging something positive, and letting the bullpen stay still.

"I was happy I came back strong, but it was too late," Armas said. "I didn't give my team a chance to win."

The Nationals nearly matched the Rangers' home run output, getting a pair of solo shots from Ryan Church, the first multi-homer game of his career, and the second in as many nights from Cristian Guzman, a two-run blast. But they meant little, and the Nationals allowed Texas's Ricardo Rodriguez -- making just his second major league start -- to keep them off balance much of the night, getting just four hits through seven innings before Guzman's homer drove him from the game in the eighth.

"When you're down 7-zip," Robinson said, "it's pretty hard to go up and do things against a pitcher that's throwing as well as that kid did tonight."

That the Rangers jumped on Armas with a barrage of homers was less than surprising, considering they now lead the majors with 107 in just 66 games. Teixeira -- who went 3 for 4 with four RBI, the homers, a walk and a double -- tied Soriano for the team lead by hitting his 18th in the first. Two minutes later, he fell one back when Soriano cranked his 19th, then tied the Rangers' second baseman -- as well as New York Yankees third baseman Alex Rodriguez -- for the American League lead by hitting his 19th an inning later.

Normally, the first option to relieve Armas would have been Kim. But just before game time, Robinson got word that Loaiza wouldn't be able to go Sunday. Loaiza -- coming off his worst start of the year in Anaheim -- said Saturday he was still battling back and neck stiffness.

"I feel better," he said before the game. "But we'll see."

The other option as an innings-eater in relief is normally T.J. Tucker. But Tucker allowed three runs in 11/3 innings in Friday night's loss to the Rangers, and was placed on the 15-day disabled list Saturday with inflammation in his right elbow.

So the Nationals, so hot for so long, now find themselves wearing down in the searing Texas heat. They lost for the second game in a row, the first time they have suffered back-to-back defeats since May 27 and 28 in St. Louis, the last two games of a five-game losing streak -- one they immediately followed by winning 13 of their next 14. They also ensured they would lose a series for the first time since they played the Cardinals; they had won five series in a row.

And they have players slumping. Third baseman Vinny Castilla, dropped to seventh in the order, went 0 for 2 -- dropping his average to a season-low .262 -- before being replaced in the sixth. Center fielder Brad Wilkerson went 0 for 3 -- dropping his average to a season-low .271 -- before being replaced in the sixth as well. And designated hitter Wil Cordero (0 for 4) is hitting .042.

To avoid just their second three-game sweep of the year, some of that must change Sunday.

"It's a little early for must-wins," Robinson said. "But we'd like to win tomorrow. . . . To me, it's an important game."

Mark Teixeira, left, is greeted by David Dellucci following Teixeira's second homer of the night, 19th of the season.