Washington Nationals manager Matt Williams and general manager Mike Rizzo continue to express optimism despite the club's six-game losing streak.

Rizzo offered a vote of confidence to his manager following Sunday's 5-0 setback to the San Francisco Giants that dropped the Nationals below .500 (58-59) for the first time since May 7.

"I have nothing but complimentary things to say about our manager since we hired him," said Rizzo after Washington lost for the 13th time in 17 games to turn a three-game lead over the New York Mets in the National League East into a 4 1/2-game deficit.

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Williams acknowledged that the Nationals have to be "better in all aspects" but dismissed the notion that the team had hit rock-bottom.

Washington has lost two-thirds of its games since the All-Star break (10-20) and the expected boost from the return of regulars Ryan Zimmeran, Jayson Werth and Anthony Rendon to the starting lineup has not materialized.

"We've played terrible over the last 15, 20 games," Zimmerman said. "We have 45 games to go and we are 4 1/2 games out. Man, we could be easily eight games out. You can take the positive out of it."

(h/t MLB.com)