Nats being careful with Span; Scherzer on mend

4/24/15: Denard Span runs a long way to make a sweet over-the-shoulder catch and rob Marcell Ozuna of extra bases in the 5th inningMIAMI -- Nationals center fielder Denard Span was given the day off Saturday against the Marlins. After playing four consecutive games, Span's legs "were really heavy. But's that's part of the process," according to manager Matt Williams.

With Span out of the lineup, Bryce Harper moved from right to center field, while Reed Johnson received a start in right field.

"What we have to be mindful of is that we don't want to push [Span] too hard, because this is a long-term thing," Williams said. "We have a lot of games left. I want to make sure he is healthy for the…