"We want to see him dial it up a little bit," Girardi said. "I think it's important that we see something."
Coming off surgery to remove a bone spur from his pitching elbow, Tanaka was lit up by the Nationals his last time out, surrendering seven runs in four innings. The 27-year-old has produced a 7.36 ERA in four spring starts.
Girardi suggested that Tanaka might be holding something back because of his past injury issues; last week, the Yankees asked him to ramp up his intensity in his between-starts bullpen sessions and carry that into games.
"Obviously, the results aren't there," Tanaka said through an interpreter. "But Spring Training is a time where you have to kind of see what you have, and sort of a time where you can test things. That's part of the reason for that. But, right now ... I'm not getting the results that I want, so I wouldn't say it's my best."
With the Yankees playing split-squad games on Tuesday, Girardi will stay in Tampa to watch CC Sabathia face the Pirates while pitching coach Larry Rothschild observes Tanaka in Clearwater. Girardi said he hopes Rothschild will report that Tanaka's splitter and slider are good, and that Tanaka located his pitches.
"I don't think his split has been as sharp. There have been some starts he hasn't thrown it a lot," Girardi said. "His slider is something that's been important to him. I think it's a guy that's a veteran guy, in a sense, even though he's not that old. He kind of takes his time easing into it, but we're pretty close to the start of the season."
Tanaka said he feels fine physically, and that he would not be upset if someone else winds up getting the Opening Day start. In theory, Sabathia would be just as rested as Tanaka, while Ivan Nova is scheduled to pitch Wednesday and would thus line up to start April 4 on regular rest. They could also have Luis Severino, who pitched in a Minor League game on Monday, start the opener on six days' rest.
"In my mind, [there would be] no disappointment," Tanaka said. "It's something that's out of my control and it's what the manager decides, so I'll go wherever they need me to go and I will be ready for that."
Girardi said he is not exactly sure what it would mean if Tanaka were unable to take the ball on Opening Day, but noted, "We have enough people who can pitch."
"There's a lot of creative things you could do," Girardi said. "Our hope is that he's really good tomorrow and it's a non-issue."