Before the Phillies bullpen allowed the Nationals to secure a comfortable lead in the eighth inning on Sunday, much of the afternoon was the Stephen Strasburg vs. Cole Hamels show. Both starters were locked in, neither giving an inch to their opponent.

Hamels was the one to blink with a run allowed in the third, though it went unearned thanks to an error by Cody Asche. Strasburg wasn't quite as generous.

The right-hander went seven scoreless, allowing just three hits and a walk to go along with 10 strikeouts. He retired the first seven batters he faced and put on a clinic of razor-sharp fastballs, twisting curveballs and a diving changeups.

“He was good, really good," manager Matt Williams said. "Lots of curveballs today, really good curveballs early in the count to get strike one. And good fastball command, as well. Probably the best fastball command I’ve seen him have all year today. And the ability to throw a breaking ball at any time sure keeps hitters off-balance. So he pitched really well.”

Strasburg used his curveball on 21 percent of his 99 pitches Sunday, a few ticks up from his 17 percent usage rate this season. Later in his start, however, it was a huge emphasis.

Strasburg threw 16 curveballs in his final three innings including seven of his 13 total pitches in the sixth against Ben Revere, Jimmy Rollins and Chase Utley. The Utley at-bat was capped off by a winding hook for the swinging strikeout.

"I felt like I had a pretty good feel for [the curveball] in the pen and just really felt like I could command it to both sides of the plate today," Strasburg said.

"He's getting better and better," catcher Jose Lobaton said. "His curveball is one of the best. He's using both sides, he's using backdoor and he's using in."

Strasburg said he made some tweaks prior to Sunday's 4-0 win with pitching coach Steve McCatty, but that he couldn't share many details about their conversation.