Werth hoping for Monday return to Nationals' lineup

PHILADELPHIA -- Nationals outfielder Jayson Werth continues to make progress on the field. On Thursday, he played seven innings for Class A Potomac and went 0-for 2 with a walk.

Werth may not be able to play Friday because of bad weather. If that's the case, Potomac will play a doubleheader Saturday, according to Nationals manager Matt Williams. Werth may play the first game in the outfield and get an at-bat or two in the second game as a designated hitter.

As of now, Werth, recovering from offseason shoulder surgery, is shooting for Monday to be his season debut against the Red Sox.

In a Minor League game in Viera, Fla., center fielder Denard Span (rectus abdominis muscle) had two hits in three at-bats and ran the bases well. On Saturday, Span will have live batting practice and play five innings in another Minor League game Sunday.

The team will then make a decision on when he can begin a rehab assignment. Span hopes to be back with the Nationals by the end of the month.

Third baseman Anthony Rendon (sprained MCL in his left knee) took ground balls right at him, according to Williams. He did some side to-side work that still bothers him a little bit. There is still no timetable when he will return to action. Rendon injured the knee making a diving play against the Braves on March 9.

"He did all of his running program … with no issues," Williams said. "So we'll look to increase the groundball load, start a throwing program and eventually a hitting program which shouldn't be far off.

Casey Jannsen (shoulder discomfort) started his throwing program on Friday, but no timetable is set for his return, either. Jannsen is slated to be one of Washington's setup men once he is back on the field.