It's hard to win baseball games when you can't score runs.  Every mistake is magnified.  Every runner left on base is another wasted opportunity.  Every pitch thrown by an overworked bullpen puts the game on the line.

The Washington Nationals found out again -- the hard way -- how difficult it is to win baseball games when you only score one run, as Matt Cain struck out 11 and the San Francisco Giants took the rubber game of this three-game series 3-1, before 41,738 on a beautiful day by the bay.

Cain (W, 5-4, 3.36) was masterful in throwing a complete game against the Nats.  He gave up one run on five hits and walked one to go along with his 11 Ks.  The only run Cain allowed was on a Rick Ankiel double, driving Michael Morse home from second after he singled and stole second base.

Nationals starter Yunesky Maya was just as good in his finest performance in a Nats uniform, giving up one run on four hits and one walk.  The one run came in the bottom of the sixth on consecutive doubles by Eli Whiteside and Cain, who drove in the first run of the game.

But Maya barely wriggled out of the sixth inning, getting a fielder's choice and ground out with two runners on, and was lifted in favor of Sean Burnett in the seventh.  That's when the Nats' troubles really started.

Burnett entered the game tied at one, and proceeded to cough up that lead.  He got two outs, sandwiched around a Cody Ross single, but lost focus against the bottom of the order and gave up a triple to rookie shortstop Brandon Crawford (41 MLB at bats) and a single to Whiteside (.190) before retiring Cain to end the inning.

Burnett took the loss (1-3) and the two earned runs pushes his season ERA to 5.96.  Once one of manager Jim Riggleman's most trusted relievers, Burnett has now given up as many earned runs this season as he did all of last season.  The most troubling aspect of Burnett's game right now is his lack of a strikeout pitch.  He is striking out just 4.8 per nine innings, well below last season's mark of 8.9 per nine innings.

Still, the Nats gave up just three runs yesterday, not an insurmountable deficit.  But the hitting continues to confound, and the Nats could muster nothing against Cain.  Leadoff hitter Roger Bernadina went 0-for-3 with a walk, his average dropping to .248.  Laynce Nix was hitless in four trips -- he's just three for his last 19 and hitting .212 in his last ten games.  Wilson Ramos, in the five-hole, went 0-for-4 was well.

And Jayson Werth missed his second straight game nursing a sore ankle after tripping on a bullpen mound in Monday night's game.

Washington is now 27-35 and 3-4 in the first seven games of the 11-game road trip they're on.  They head to San Diego for a four-game weekend series, then return home to play 20 of their next 26 games at Nationals Park. 

THE GOOD:  Maya's outing will probably keep him in the rotation for now.  After two straight shaky performances, falling apart in the third trip through the opposing lineup, Maya was solid and Riggleman got him out at the right time.

THE BAD:  The offense.  five hits and one walk just isn't going to cut it.

THE UGLY:  Matt Stairs looked at strike three in his only at bar, lowering his average to .108. He's 4-for-37 this season with seven walks, 12 strikeouts and zero RBIs

THE STATS:  Five hits, one walk, 11 strikeouts. 1-for-6 with RISP, five LOB, 0 GIDP. No errors.

NEXT GAME:  Thursday v. San Diego Padres at 10:05 pm from Petco Park.  Livan Hernandez (3-7, 3.76) faces Aaron Harang (6-2, 3.77).