SAN DIEGO -- The San Diego Padres have struggled this season against teams with winning records this season, going 11-24.

This problem comes into play the next four days as the Washington Nationals, the team with the National League's second-best record, visit the Padres at Petco Park. And if you happen to be the Nationals, this is opportunity knocking.

Having just dropped two of three games at home to the third-best team in the NL East -- the Miami Marlins -- the Padres face the division leaders, who have won eight of their last 10.

More from FoxSports

"We've got our work cut out for us," Padres manager Andy Green said last Sunday as his team headed back to Petco for a seven-game homestand.

About the only thing that might be considered a break for the Padres isn't a break from the business end. The Padres won't be facing native San Diegan and San Diego State product Stephen Strasburg, who started for the Nationals Thursday in Washington's 5-4 win over the Cubs. The Padres were looking forward to Strasburg drawing a larger crowd than usual to Petco.

But they will be facing one of their own in a sense. Former first-round draft pick Joe Ross is scheduled to start against the Padres on Friday night. Ross and another first-round pick, shortstop Trea Turner, went to the Nationals on Dec. 18, 2014, in the three-team, 11-player trade that brought first baseman Wil Myers to the Padres.

First things first.

The four-game series opens Thursday night with right-hander Erik Johnson makes his second start for the Padres against Washington right-hander Tanner Roark (5-4, 2.93 ERA).

Johnson was obtained from the Chicago White Sox on June 4 in the trade that sent right-hander James Shields to the White Sox. Both pitchers have struggled for their new teams.

Johnson made his Padres debut last Saturday afternoon at Coors Field in Colorado. He gave up five runs on nine hits and two walks in just 4 2/3 innings. Two of the hits were home runs. The Rockies jumped Johnson for three runs in the bottom of the first after the Padres had given him a 2-0 lead.

Plus, the Padres have struggled in the past against the 29-year-old Roark, who has a 2-0 record with a 0.45 ERA against the Padres in three previous meetings (two starts). At Petco, Roark has given up one run on four hits over 11 innings. Padres batters who have faced Roark before are a combined 4-for-41.

"We've been catching a lot of good pitchers and Washington has five quality starters," Green said.

Meanwhile, no member of the Nationals has faced Johnson, who bounced between the White Sox and Triple-A over the past several seasons.

"He's deserving of an opportunity to show what he can do, which is what we're offering," said Green.