The Washington Nationals took off when Denard Span returned from injury in mid-April, going 20-13 with the center fielder in the lineup.

They went 8-9 without Span and have scored more than a full run more (4.94 to 3.82) when he's active.

The trend isn't entirely new. Since Span joined the Nationals in 2013 they are 186-136 when he starts and 24-28 when he doesn't.

Washington has several important pending free agents -- including Jordan Zimmermann, Doug Fister and Ian Desmond -- but Span may be the most important.