CHICAGO -- Jacob Arrieta wasn't as sharp as he would've liked. Addison Russell admitted a grounder took a funny hop on him. Wade Davis threw a pitch he'd like to have back.
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They all contributed to the Cubs' 5-0 loss to the Nationals on Wednesday in Game 4 of the National League Division Series presented by T-Mobile, now tied at two wins apiece. Game 5 will be played Thursday night at Nationals Park.
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Arrieta was pushed back in the postseason rotation to give him more time to nurse a right hamstring, and he was pitching for the first time since Sept. 26. The layoff might have affected him.
"I was a little erratic," said Arrieta, who allowed an unearned run, two hits and walked five in a 90-pitch outing over four innings. "Emotions were high, energy level was at a pretty high level in this situation. I wasn't going to give in and make mistakes and allow them to do damage, especially with multiple hitters in a row. Walks were up, but when it came down to it, I made pitches when I had to, to preserve the situation."
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Arrieta did strike out Daniel Murphy to end the third, stranding two runners, and he also got Jayson Werth looking at strike three to leave the bases loaded in the fourth.
"I knew it would be an adjustment when I first took the mound," Arrieta said. "I walked five guys and the erratic nature tonight probably had something to do with the extended layoff but also the playoff atmosphere."
Arrieta also took a moment before the game to soak it in. The right-hander will be a free agent this offseason, and if the Cubs don't advance, this might have been his last start for the team.

"Absolutely," Arrieta said. "Before the game, warming up in the outfield, I just tried to take it all in. The weather, very indicative of October baseball. Some rain, some fairly chilly weather, nothing too crazy."
But Arrieta couldn't celebrate a victory.
Russell's miscue came in the third. The Nationals had runners at first and third with two outs when Ryan Zimmerman hit a grounder to the shortstop, who charged the ball but couldn't get his glove on it. A runner scored and Russell was charged with an error.

"I thought the ball was going to stay down a little bit more," Russell said. "It just skipped up a little bit. Normally, I make that play. You've got the elements to work with and just trying to slow the game down as well. That's a play, I make that play routinely."
That 1-0 lead was all Nationals starter Stephen Strasburg needed as he struck out 12 over seven innings, giving up two hits. Russell thought he had a home run in the second inning when he launched a fly ball to left, but Jayson Werth caught it at the wall.
"Any other day it would be out," Russell said. "That's the name of the game. I really wish that ball would've left, because it would've been a different ballgame."
Michael A. Taylor found a way to hit one out despite the drizzle, cold and wind. He connected on a grand slam in the eighth off Davis, only the second homer off the right-hander in 26 postseason appearances and first since his first playoff game in 2010 with the Rays when he started an American League Division Series game.
"That ball had to be absolutely crushed," manager Joe Maddon said of Taylor's blast. "That's into a gale, high, opposite field, all those factors are involved. That surprised all of us, obviously."

"That particular pitch, I tried to go down, and I almost threw it down the middle," Davis said. "It was a bad pitch. It was down the middle and he put a good swing on it. I'd definitely like to have it back."
So would Arrieta. So would Russell.