Now, the Japanese rookie will look to build on the best outing of his brief career as the Yankees open a four-game home series with the Seattle Mariners on Friday.Igawa (2-1, 6.08 ERA) had his last start skipped after allowing seven runs in 4 1-3 innings in a 10-8 loss to Tampa Bay on April 23. However, he pitched six-plus scoreless innings in relief in Saturday's 3-1 win over Boston after starter Jeff Karstens was hit in his leg by a line drive on the first pitch of the game, helping the Yankees (12-14) end a seven-game losing streak."A game like today, for me, gives me confidence that Kei is going to understand what we've been telling him," pitching coach Ron Guidry, whose rotation has been plagued by injuries, told the Yankees' team Web site. "If you make these pitches consistently, you're going to win. It's that simple."The Yankees spent $46 million to bring Igawa, who pitched exclusively from the stretch against the Red Sox, from Japan in the offseason. He allowed seven runs in two of his first four starts, while his other win came in a 9-2 victory over Cleveland on April 18 in which he lasted six innings."That's what this game is all about -- being able to repeat," manager Joe Torre told the Yankees' site of Igawa. "That's when you start relying on people. Not that they don't give you a good effort, but it's that the results, the stuff, the command and all that stuff are there on a regular basis. That's what we are looking for right now."Igawa's win started a 4-1 stretch for the Yankees, who won both games of Thursday's doubleheader with Texas to sweep a three-game series. Andy Pettitte pitched six strong innings in the first contest, a 4-3 victory, and Mike Mussina returned from the disabled list to earn the 5-2 win in the second.Mariano Rivera earned a save in both games after entering the game with only one."We had a little extra attitude this week," said Doug Mientkiewicz, who homered in the second game. "Not that we were freaking out, but it was like, let's put our foot on the gas a little bit."Derek Jeter went 4-for-9 in the doubleheader and is hitting .364 (32-for-88) with 17 runs during a 20-game hitting streak.The Yankees have won six of their last seven at home against the Mariners (12-11), who are coming off Thursday's 8-7 loss at Boston. Jose Guillen had three hits and two RBIs, and Yuniesky Betancourt had two hits and also drove in a pair of runs for Seattle, which lost for just the second time in nine games.Ichiro Suzuki set an AL record with his 41st straight successful stolen base.Cha Seung Baek (0-0, 4.22) will look to help the Mariners bounce back. He took a no-hitter into the sixth inning in his last start but did not receive a decision despite allowing just one run and four hits in 6 1-3 innings of Seattle's 5-1 win over Kansas City on Sunday.However, Baek, who was brought up from Triple-A Tacoma on April 23 after Felix Hernandez went on the disabled list with a strained forearm, did make a case for remaining in Seattle's rotation and could replace Jeff Weaver once Hernandez returns.Baek's only previous start against the Yankees came on Aug. 22, when he allowed three runs in five innings without receiving a decision in Seattle's 6-5 home win.