"I love two-out runs," Cubs manager Joe Maddon said. "They really hurt the other side badly. Conversely, when it happens to you, you're constantly [thinking], 'Can we make a better pitch right there? Did we call the right pitch right there? Did we execute the pitch right there?' The two-strike knocks can really bum you out a little bit. When you get them, there's nothing more glorious than that."
Wood served up five hits, including a two-run homer by Starling Marte in the fourth, and struck out a season-high nine batters over seven innings. Kris Bryant and Starlin Castro each drove in a run for the Cubs, who now have won 11 of their last 16 games, and are off to their best start (12-7) since going 13-6 in 2008.
Jeff Locke took the loss, giving up six runs -- five earned -- on eight hits over 3 2/3 innings. The Pirates came into this series riding a five-game winning streak, and have now dropped two straight.
"We weren't able to get in control of any aspect of the game," Pirates manager Clint Hurdle said. "This one, it felt like more than 6-2."
MOMENTS THAT MATTERED Two-out hitting: The Cubs had scored their previous seven runs over two games with two outs, and continued that trend on Tuesday. In the second inning, Chicago had runners at first and third with two outs when Addison Russell hit an RBI double. Fowler, who was 0-for-10 against lefties coming into the game, followed with a two-run single to open a 3-0 lead. With two outs in the third, Junior Lake added an RBI double, and with two outs in the fourth, Bryant hit an RBI single.
Cubs running wild: The Cubs pulled off two double-steals in the fourth inning, the first time they've swiped four in one inning since doing so in the first vs. Montreal on Aug. 23, 1997. Chicago now has 25 stolen bases for the season, most in the National League. More >
Marte mashing lefties: Marte began Tuesday with 25 strikeouts in 19 games, the plate discipline that made him so effective down the stretch last season having seemingly vanished. But he has continued to produce against lefties. The left fielder took Wood deep to left field in the fourth inning, cutting the Cubs' lead in half with a two-run shot, his sixth of the season.
"He does a good job getting his swing off and finding the barrel against [lefties]," Hurdle said.
"Their execution. Our lack of execution. That's a bad combination to be in." -- Hurdle, on the difference in the game
"Everyone's more upbeat. We're not 10 games under .500 going into May. We've got a good group. You come to the ballpark and enjoy each other and pick up each other and have fun." -- Anthony Rizzo on Cubs
SOUND SMART WITH YOUR FRIENDS
• Rizzo stole his sixth base of the season as part of a double steal in the fourth. The six stolen bases matches his single-season career high, set in 2013.
• The Cubs clinched their first series win against the Pirates since July 5-6, 2013, at Wrigley Field.
The Cubs entered the game 0-for-5 in challenges this season but went 2-for-3 on Tuesday. In the second inning, Castro was originally called out after hitting a grounder to shortstop Jordy Mercer, but after a review, the call was overturned and Castro was credited with an infield single.
Corey Hart was on second with two outs in the Pirates' sixth when Marte singled to left. Lake threw to Bryant at third, and he tagged Hart, who was originally called safe. But the call was overturned after a review and the inning was over.
In the Chicago eighth, Castro was called out trying to steal second base, and Maddon challenged it as well but after a review, it was ruled that the call would stand.
WHAT'S NEXT Pirates: Right-hander Gerrit Cole will look to continue his unbeaten start in Wednesday's series finale against the Cubs at Wrigley Field at 8:05 p.m. ET. Cole, 3-0 with a 2.19 ERA, allowed one run and struck out seven D-backs hitters over 7 2/3 innings on Friday in Arizona. Cole is 5-0 with a 3.48 ERA in five career starts against the Cubs.
Cubs:Kyle Hendricks will close the Cubs series against Pittsburgh on Wednesday. The right-hander is coming off a no-decision against the Pirates in his last start, when he gave up three runs on five hits over 5 1/3 innings. Hendricks is still looking for his first win of the season. First pitch is scheduled for 7:05 p.m. CT at Wrigley Field.