WASHINGTON -- Michael Morse hit a grand slam, Bryce Harper also homered and the Washington Nationals became the latest team to tag a struggling Johan Santana in their 6-4 victory over the New York Mets on Friday night.
Ross Detwiler (7-5) tossed six solid innings and the Nationals sent Santana to his fifth loss in the last five starts.
Handed a 2-0 lead, the two-time Cy Young Award winner was perfect through three innings. But the NL East leaders strung together four consecutive hits in the fourth, capped by Morse's 12th homer.
Harper added a two-run shot in the fifth. Tyler Clippard earned his 26th save.
The Nationals, who own the best record in baseball, have won 10 of 12 overall.
The Mets fell to 10-23 since the All-Star break and have dropped 10 of 13 to the Nationals this season.
Santana (6-9) permitted six runs and seven hits over five innings. He has a 15.63 ERA in his past five starts, allowing at least six runs in each appearance.
REDS 7, CUBS 3
Bronson Arroyo (9-7) overcame a shaky start to improve to 5-1 in his last six outings. He gave up nine hits and three runs in 6 1-3 innings.
The NL Central leaders have won six of seven. They had six extra-base hits in five innings against former teammate Travis Wood (4-9), who has lost his last six decisions after winning four straight starts.
Copyright 2012 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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