WASHINGTON -- The biggest mistake the Nationals made Wednesday wasn't Jonny Gomes' bobbled ball in left field. And it wasn't either of the pitches Livan Hernandez threw to allow eighth-inning singles that proved the difference in a 4-2 loss to the D-backs.
For manager Davey Johnson, it was that Hernandez was out there in the eighth in the first place.
"I take responsibility for that one," Johnson said. "He was really pitching a great game and when he's good, he's really good. I had it in my mind that if he gives me seven, I'm getting him out of there. I balked. He got into trouble and couldn't get out of it."
It was "vintage Livo," according to Ryan Zimmerman, as Hernandez worked his way into and out of trouble with just 83 pitches through the first seven innings.
So he returned for the eighth and got opposing starter Daniel Hudson to fly out to start the inning. Ryan Roberts singled and took third on Gerardo Parra's base hit, which allowed Parra to advance on the throw. Hernandez intentionally walked Justin Upton to load the bases, then turned it over to Henry Rodriguez.
"I really don't like to bring Henry in with men on base," Johnson said.
But with Hernandez in trouble, that was his only option. Rodriguez started Miguel Montero with a 97-mph fastball, then threw a 91-mph changeup that Arizona's catcher smacked into right field for a two-run single and a 4-0 lead.
"I know that kid's got a pretty good fastball, so I was trying to catch up on the fastball, and he threw me a changeup and I got a little bit in front," Montero said. "But it was a beautiful hit."
It first appeared as if it would only be insurance, as Hudson stifled the Nationals all night, but it was ultimately the difference.
Hudson was an out away from his first career shutout before Laynce Nix and Gomes belted back-to-back homers on consecutive pitches in the ninth.
"Solo home runs aren't going to win many ballgames," Gomes said.
But that was the only offense Washington mustered against the right-hander, who struck out six over 8 2/3 before closer J.J. Putz recorded the final out.
It looked like Washington might get to Hudson early, but he stranded four runners on base through the first three innings, then retired 13 batters in order. Nix snapped the streak with a seventh-inning double into the right-field corner, but Hudson escaped the jam by catching Gomes looking at a 95-mph fastball.
"That pitch I hit [for a home run] was probably the only pitch I had to drive all night," Gomes said. "Cutter, slider, change, both sides of the plate, power -- I tried to work him, but he was making pitches when he had to."
One of those came in the eighth inning, which Wilson Ramos led off with a single before Ian Desmond doubled with one out. But Rick Ankiel lined out to first base and Zimmerman was robbed of a base hit by shortstop John McDonald.
"It's the second night in a row we didn't really come out offensively -- a little too late," Desmond said.
And while Washington left men on, the D-backs capitalized on limited opportunities against Hernandez.
Upton singled with one out in the fourth, then scored from first on Chris Young's double into the left-field corner. Gomes chased the ball down and bobbled it, allowing Upton to score easily. Lyle Overbay followed with an RBI single to put Arizona ahead by a pair.
"Some days, you're going to get beat," Zimmerman said. "That's what that team is known for. They don't score many runs, but they get big hits when they need them and their pitching staff carries them. The last two games, that's what they've done to us."
Steven Miller is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.