The slugger is hitless in three at-bats and has walked three times overall.
"I feel like I have six at-bats," Harper said. "Still got to get going and get my timing right. That's the biggest thing. I think I'm seeing it pretty well. Just got to get timing."
Harper received a mixture of applause and boos from the packed crowd at Steinbrenner Field when he was announced before a first-inning at-bat that ended with a grounder to first base.
Harper, who homered for his only hit in five regular-season at-bats against Tanaka, struck out swinging on the eighth pitch of his at-bat in the third.
The strikeout came on an 89 mph splitter.
"Not just him, I think the whole lineup was close to their Opening Day starting lineup," Tanaka said through a translator. "So, it's always good to be able to pitch against guys that will regularly start a game, and you obviously always want to do good against those guys."
Tanaka allowed two runs, six hits and struck out six over 3 2/3 innings cheap championship rings.
Facing reliever Adam Ottavino in the fifth, Harper was awarded first base on catcher's interference and then stole second.
"I said, 'Hey, it's spring training, can I stay here?'" Harper said. "[The umpire] said get to first. I tried. I would have liked to get that last at-bat, for sure."
Harper left Washington as a free agent and signed a record 0 million, 13-year contract with Philadelphia this month.
"Bryce being here and bringing this attention, I think, has a chance to create higher expectations, which can create a higher level of play from our guys," Phillies manager Gabe Kapler said. "And also I think it separates the guys who play with the brightest lights from the guys who can't, and I think that's a great thing for our ballclub."
Harper walked twice against Toronto on Saturday. He took a 96 mph fastball for strike three from American League Cy Young Award winner Blake Snell and drew a walk from Jalen Beeks in Monday's game against Tampa Bay.
Harper talked with Hall of Famer and Yankees adviser Reggie Jackson, who told the six-time All-Star that he is important to the game.
"Definitely humbling," Harper said. "Just to be able to stand there and talk to him and hear what he had to say, it's pretty incredible."
