Washington @ Chicago preview

Last Meeting ( Jun 20, 2010 ) Chi. White Sox 6, Washington 3

THE STORY: The red-hot Washington Nationals begin the post-Jim Riggleman era Friday when they open a three-game interleague series against the Chicago White Sox at U.S. Cellular Field. Bench coach John McLaren will guide the Nationals following Riggleman's stunning resignation after Thursday's victory over Seattle, a decision made due to his unhappiness with his contract situation. Riggleman quit after Nationals general manager Mike Rizzo refused to discuss the possibility of picking up the manager's 2012 option. Washington just completed an 8-1 homestand and has won 11 of its last 12 games overall. Chicago has won seven of its last 10 home games and 17 consecutive interleague series.

TV: 8:10 p.m. ET, MASN (Washington), CSN (Chicago)

PITCHING MATCHUP: Nationals RH Jordan Zimmermann (5-6, 3.08 ERA) vs. White Sox RH Edwin Jackson (4-6, 4.47 ERA)

Zimmermann has won three consecutive decisions overall and is 2-0 with a 0.86 ERA in his last three outings on the road. The 25-year old allowed two runs over 6 1/3 innings in a victory over Baltimore on Saturday but was forced to settle for a no-decision at San Diego on June 12, when he struck out 10 in seven scoreless frames.

Jackson is 0-1 in four starts since posting a victory over the Los Angeles Dodgers on May 22. The 27-year old is coming off a 4-1 loss at Arizona last Friday in which he allowed four runs over 6 2/3 innings but struck out eight without a walk. Jackson is 5-5 in 17 career interleague starts but has won four of his last five decisions.

ABOUT THE NATIONALS (38-37): Washington completed a three-game sweep of Seattle on Thursday, winning all three contests by one run. The 1-0 triumph Thursday was the club's ninth victory this season when scoring two runs or less. Seven of those wins have been 2-1 decisions. Washington has won four straight series and five of its last seven (5-1-1) since May 30. The Nationals have not been above the .500 mark this late in a season since 2005.

ABOUT THE WHITE SOX (37-39): Chicago has not dropped an interleague series since being swept in a three-game set by the cross-town Cubs from June 22-24, 2007. DH Adam Dunn will face the Nationals for the first time since leaving the club after two seasons. The slugger's nightmarish first campaign with the White Sox includes 91 strikeouts in 64 games, a total that leads the American League. He fanned a career-high 199 times in 158 contests with Washington in 2010 and 177 times in 159 games the previous year.

FINAL PITCH: "I just wanted to have a conversation when we got to Chicago about it, and (Nationals GM Mike Rizzo) said he's not ready to have that conversation. I said, 'I've got to give it up then. I'm obviously not the person that you all want to go down the road with, and I get that, that's OK.'" -- Riggleman on his resignation due to his contract status.