By C. Trent Rosecrans
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Pulling away: The National League's closest race is on the verge of being decided -- the Diamondbacks can take a commanding seven-game lead in the NL West with 23 games remaining with a victory in Sunday's series finale at AT&T Park in San Francisco. Arizona's Daniel Hudson looks for his 15th victory of the season and third straight. In his last four starts, he's gone 3-1 with a 2.43 ERA, pitching seven scoreless innings in his last start, a win over Coloardo. He's just 1-2 against the Giants this season, but limited them to a run on six hits in a victory at AT&T Park on Aug. 6. Giants starter Ryan Vogelsong has lost each of his last three starts and four of his last five. Diamondbacks at Giants, 4:05 p.m. ET
Welcome back: Rangers left-hander Matt Harrison will get another chance against the Red Sox, returning to the team's rotation to face the same team that roughed him up in his last start. Texas manager Ron Washington inserted Scott Feldman into Harrison's spot in the rotation last week and used Harrison in relief on Wednesday. Harrison gave up seven earned runs on 11 hits in five innings on Aug. 24 against the Red Sox, prompting Washington to give the 25-year-old a short break. Harrison had a 3.04 ERA before the All-Star break and 4.56 afterward, so the Rangers hope the time off returns him to his pre-break form. Red Sox starter John Lackey hasn't had much success against the Rangers, either. In two starts against Texas this season, he's given up 13 earned runs in 10 1/3 innings. Rangers at Red Sox, 1:35 p.m. ET
Cy Kershaw: While the American League Cy Young race is about as excited as most of the races around baseball right now (read: not very), the National League competition has heated up because of the performance of Dodgers lefty Clayton Kershaw. The 23-year-old is 17-5 with a 2.45 ERA overall and 8-1 with a 1.32 ERA since the All-Star break. Kershaw has won his last four starts, allowing just two runs in those four games. Kershaw has five starts to win three games and become the Dodgers' first 20-game winner since Ramon Martinez won 20 in 19990. Dodgers at Braves, 1:35 p.m. ETFor more baseball news, rumors and analysis, follow @cbssportsmlb on Twitter or subscribe to the RSS feed.