Colorado @ Washington preview

Last Meeting ( Jul 9, 2011 ) Colorado 2, Washington 1

THE STORY: After beginning their seven-game road trip with four straight losses at Atlanta, the Colorado Rockies attempt to complete a three-game sweep of the Washington Nationals on Sunday. Colorado still is struggling to produce runs as they have scored three or less in each of its six games on the trip thus far. Washington, which has totaled three runs over the first two games of the series, is hoping to enter the All-Star break with a .500 record.

TV: 1:35 p.m. ET, Root Sports (Colorado), MASN2 (Washington)

PITCHING MATCHUP: Rockies RH Jhoulys Chacin (8-6, 3.28 ERA) vs. Nationals RH Jordan Zimmermann (5-7, 2.82).

Chacin is seeking his first win in four starts. The 23-year old allowed four runs over five innings at Atlanta on Tuesday in suffering his second straight loss. Chacin enters Sunday with a .203 batting average against, the second-lowest in the National League this season. Zimmermann is coming off a no-decision against the Chicago Cubs on Monday in which he yielded four runs over six innings. It marked the first time in 12 starts the 25-year-old allowed more than three earned runs. Zimmermann, who is only 2-4 in seven home outings this year, has pitched 108 2/3 innings in 2011 and is expected to be limited to 160 in his first full season since undergoing Tommy John surgery.

ABOUT THE NATIONALS (45-46): Washington fell to 5-5 on its season-high, 11-game homestand. Lefthander John Lannan expects to make his next start Saturday. He suffered a nasal contusion in the fourth inning of Friday's game when he was hit in the face by a line drive. The Nationals have lost three straight contests, each by one run. They are 13-6 in one-run games since June 1. Shortstop Ian Desmond singled and tripled Saturday for his first multi-hit performance since June 17. Michael Morse notched his third multi-hit effort in four contests and eighth in 15 games.

ABOUT THE ROCKIES (43-47): Righthander Ubaldo Jimenez became Colorado's all-time leader in strikeouts Saturday. Jimenez fanned eight Nationals to give him 750 strikeouts, one more than Pedro Astacio. Outfielder Carlos Gonzalez did not start because of soreness in his right wrist and is also expected to miss Sunday's game. Gonzalez missed four straight games with a bruise before returning to the lineup Friday. Shortstop Troy Tulowitzki went 1-for-3 after sitting out four games with a quadriceps injury.

FINAL PITCH: Saturday's win was Jim Tracy's 200th as Colorado manager. He became the third skipper in franchise history to reach the plateau, joining Clint Hurdle (534) and Don Baylor (440).