CHICAGO -- Journeyman Cody Ransom may have finally found a home.
Ransom hit a tiebreaking, three-run homer in the seventh inning and Jackson pitched the Cubs to a 4-1 victory over the Pittsburgh Pirates on Sunday.
"He's doing everything and more than what we expected when we picked him up," Cubs manager Dale Sveum said of Ransom, who has been with eight teams in 11 seasons.
Ransom connected off reliever Justin Wilson (5-1) for his sixth home run of the season. Darwin Barney and Julio Borbon were on base after the Cubs were held hitless for 5 2/3 innings by Pirates starter Jeff Locke.
"I'm playing a little more consistently than I ever have," Ransom said. "Last year with the Brewers I got to play a little bit but that was the most I've ever played.
"I know if there's a lefty pitching I'm going to be in there more times than not. Dale has made it kind of easy for me preparing."
The Cubs' right-handed hitting, platoon third baseman had alertly taken an extra base in the sixth, leading to a game-tying run after he had been picked off in the third following a walk. His run tied the game for Jackson, who was trying to avoid the frustration of a ninth loss.
Edwin Jackson (2-8) had his best and longest outing of the season, striking out eight in seven innings. He allowed four hits and a walk as the Cubs salvaged the finale of a three-game series.
"Sometimes we take the game too serious and we are kind of confined in a bubble," Jackson said. "Today I was just able to come out of that bubble and have some fun out there.
"Maybe taking it too serious is kind of a way to describe it."
Kevin Gregg pitched the ninth for his seventh save in seven chances, completing a six-hitter as the Cubs avoided a sweep of the three-game series.
Chicago manufactured a game-tying run in the sixth before Dioner Navarro got the team's first hit on a two-out single to left.
Ransom's alert baserunning led to the tying run. He went from first to third on an infield grounder and later scored on Scott Hairston's sacrifice fly.
"He's a gamer," Jackson said about Ransom. "When he's out there he's playing to win. He's an aggressive player.
"He took advantage of the situation to go from first to third. That's the kind of player he is."
Locke issued a leadoff walk to Ransom in the sixth. Pirates second baseman Neil Walker fielded Anthony Rizzo's grounder in the hole and had to race to the bag to get the putout because first baseman Garrett Jones was out of position trying to field the ball. No one covered third on the play and Ransom took the extra base. After Alfonso Soriano walked, Hairston's sacrifice fly to center made it 1-all.
Pittsburgh took a 1-0 lead in the fourth when Andrew McCutchen doubled and Jones followed with an RBI single.
Locke was wild all game, walking a season-high seven while striking out six. He left with a one-hitter and the game tied at 1 after 100 pitches in 5 2/3 innings.
"I didn't really know that I didn't give up any hits because there was somebody on base every inning," Locke. "Multiple people the whole time. I was pitching from the stretch no matter what.
"Good and bad at the same time. I'll take the things I did good and push forward."
Wilson allowed Ryan Sweeney's single in the seventh, and pinch-hitter Borbon bunted into a force at second. Barney singled and Ransom followed with his three-run drive.
"I just have to make a better pitch there," Wilson said. "Good job of hitting.
"I didn't get it far enough in there and he got the barrel to it and it got up in the jet stream and the ball went out."
The Pirates pitched well otherwise throughout the series. They held the Cubs to two earned runs through the first 23 2/3 innings of the series.
Navarro reached base four times, walking twice and singling twice. ... The Cubs failed to get a hit in each of the series' three games until at least the fifth inning. ... Barney moved back into the leadoff spot. He had batted eighth from the season's second game until three games ago, hit leadoff twice and then returned to eighth Saturday. ... Pirates manager Clint Hurdle said pitcher Charlie Morton could soon be considered for a return to the team after throwing 96 pitches in 6 1/3 innings Saturday during a rehab assignment with Triple-A Indianapolis. Morton had elbow surgery and has been on the disabled list since March 22. Hurdle called it the right-hander's "best outing to date." ... Pittsburgh right-hander Gerrit Cole makes his major league debut when the Pirates return home for six games starting Tuesday. The first pick in the 2011 draft will square off against San Francisco's Tim Lincecum (4-5, 4.75 ERA). ... The Cubs host Cincinnati on Monday, with Scott Feldman (5-4, 2.84) opposing Reds RHP Homer Bailey (3-4, 3.84).