WASHINGTON (AP) Nationals center fielder Denard Span has experienced a setback in his rehabilitation from a back injury, delaying his return from the disabled list.
Span, sidelined since July 7, had been hitting, running and working in the outfield lately. He felt good at first, but manager Matt Williams said Saturday that Span's back stopped getting better.
''He's had a setback. It just hasn't been progressing the way he wants it to progress,'' Williams said. ''He tried to push it this week. He just couldn't get there. It's tight. It's just not allowing him to move forward as he wants to.''
Williams said Span will stay with the team in Washington for the next few days and then go to Florida early next week for more rehab work.
While key hitters Anthony Rendon, Ryan Zimmerman and Jayson Werth have recently returned from injuries, the second-place Nationals are still missing their speedy leadoff man.
Span is batting .304 with five homers, 22 RBIs and 11 steals this season. He has scored 37 runs and hit 15 doubles.
In other news, the Nationals placed backup second baseman Dan Uggla on the 15-day disabled list with back spasms.
The move opened a roster spot for right-hander Stephen Strasburg, who came off the DL to start Saturday night against Colorado. He had been sidelined with an oblique injury.
Uggla is hitting .191 with a homer and 14 RBIs in 110 at-bats. Williams said he wasn't sure how long the infielder will be out.
''(Uggla) has been bothered by it for days now,'' Williams said. ''You try to get it loose, and it's been difficult for him.''