WASHINGTON -- Starting pitching has been the foundation of the Nationals' success since their first postseason run in 2012. Strengthening the staff seems likely to be the next target on the offseason to-do list for general manager Mike Rizzo.
Rizzo began his pursuit of a starter last week in D.C., when he and team owner Mark Lerner went to dinner with free-agent left-hander Patrick Corbin, whom Rizzo referred to as one of the elite players on the market.
• Nats meet with prized FA lefty Corbin
"We had a nice discussion with him," Rizzo said. "I had a personal discussion with him. He wanted to come down and see what we had down here and visit the city and the clubhouse. I thought that was a positive reaction by him. I'm not going to read too much into it. He's a guy that obviously we're interested in and would fit nicely on this team."
Corbin would slot alongside Max Scherzer and Stephen Strasburg in the Nationals' rotation, making it an unquestioned strength for Washington once again. But the Nats' interest does not stop at Corbin, as Rizzo has said he will "keep all avenues open" to find a starter. The Nats think highly of Dallas Keuchel and are expected to check in on the market for Nathan Eovaldi, according to a source, and they will explore the lower tiers of the free-agent market, as well.

"Starting pitching is king," Rizzo said. "Our philosophy is pitching, defense, athleticism. That's how we've won. When we put our guy on the mound [and he], each day, gives us a chance to win, you've created yourself a chance to have a really good ballclub and play deep into October.
"That's our philosophy. There's different ways to do this. We've seen the 'bullpenning' and that type of thing in playoff baseball, and that's fine. But for the marathon that is the season, you better have some starters that you can run out there and give you a chance to win each and every day. That's what we've always tried to do here."
Last season, the Nats' rotation posted a 4.03 ERA, good for ninth among starting rotations in the National League -- Washington's lowest finish since 2010. Injuries to Strasburg and Jeremy Hellickson were crippling because the team did not have the depth to compensate, and because Giovany Gonzalez and Tanner Roark struggled at the same time.
As currently constructed, the Nats' rotation is filled with questions -- aside from Scherzer, their ace who just finished second in the voting for the NL Cy Young Award.

When healthy, Strasburg is still capable of pitching at an elite level, but he required two separate stints on the disabled list last season, limiting him to 22 starts. He pitched well during the final month of the year, producing a 2.60 ERA with 11.7 strikeouts per nine innings in his final six starts, but his fastball velocity dipped from the upper 90s to the mid 90s. The Nats remain confident that the velocity will return next season, but it is worth keeping an eye on.
Gonzalez is a free agent. Roark would be the Nats' third starter if the season began today, and while the team still thinks highly of him, this will be an important year after posting an ERA above 4.30 in three of the past four seasons.
The fourth and fifth starter spots are open, with current in-house candidates including Joe Ross, who made three starts in September after missing more than a year with Tommy John surgery, and Erick Fedde, one of their prized young arms who has not been able to put together any extended success in the Majors.
"Our best month, we were [19-7]," manager Dave Martinez said, referring to the Nats' record in May. "If you look at that month, our starters were unbelievable. They were going 6 2/3 innings, seven or eight innings, and we played really well. We need that. I've said that before. Starting pitching and defense win a lot of games.
"Mike, he'll get something done. Right now, we've got three, four good starting pitchers. We could add one more, maybe two, who knows? I know Mike is working diligently to get another guy."