Of sore groins, Griffeys, birthday cakes and baseball cards (lineups)

One month from today, it all starts for real. The Mariners open the regular season April 5 at Oakland.

And that’s a really good thing if you’re David Aardsma, or the team that needs David Aardsma to close games like he did last year. He’s laying low after feeling tightness in his groin on the last pitch he threw in the third inning Thursday.

The Mariners never believed it was anything more than a minor thing, but a groin issue is nothing to ignore. Aardsma was walking around the clubhouse without a limp this morning after a session ice, stimulation and time in the whirlpool.

He realized first thing this morning, when he took at first step out of bed, that he would be OK.

“It actually put a smile on my face,” he said.

Even though the Mariners appear to have dodged a big one, Aardsma will take it easy for a while. He suffered a major groin injury two seasons ago with the Red Sox. Aardsma said this is in the same leg, the right, but farther down than before.

“This is totally different. That one was way worse,” he said. “There was a pop and I went on the DL twice. With this, I just want to be smart about it. There’s no point pushing it. We’ve still got a month until the season.”

And now, other matters of importance this morning:

—It’s double-dip day, with the Mariners facing the Padres in the big stadium this afternoon. The other game in town, this morning on a practice field, will be just as important … maybe moreso. That’s when Cliff Lee and Felix Hernandez will pitch a simulated game, Lee throwing two innings and Hernandez one.

Why the difference? Manager Don Wakamatsu said Lee has thrown close to 50 pitches in each of his past two bullpen sessions. Pitching coach Rick Adair assurred that there’s nothing wrong with Hernandez, and there’s plenty of time to get him ready for opening day.

—Around Ken Griffey Jr.’s locker, it looked a lot like 1989 again. Trey Griffey, Junior’s 16-year-old son, is in town still looking a lot like his dad did when he was a teen phenom. Junior said Trey has grown about five inches since last year, and he’s definitely taller than Dad.

Someone asked who’s the most impressive Griffey these days, and Trey quietly thumped his chest and said, “Me.”

Junior beamed. “My Dad had a t-shirt once that said, ‘I don’t take the credit. I just take the responsibility,’” he said.

—Griffey swiped Eric Byrnes’ No. 1 jersey and carried it into Wakamatsu’s office. “If (Yankees manager) Joe Girardi can get 28 because they’re going for 28 championships, then I can put No. 1 in Skip’s locker.”

Yeah, but what number will Byrnes wear? “He can have 2,” Griffey said.

Then what about Jack Wilson? “He gets 3.”

If this plan unfolds, then a bunch of guys will be changing jerseys. Ryan Garko wears 3, Jose Lopez 4, Mike Sweeney 5, Chris Woodward 6, Jack Hannahan 7, Lee Tinsley 8, Chone Figgins 9. Nobody wears No. 10.

—There’s a birthday cake on the counter in the middle of the clubhouse, with two candles shaped like the numbers 2 and 1. Looks like left-handed pitcher Mauricio Robles will be the center of a team ceremony.

—On the other side of that counter, reliever Mark Lowe carefully opened mail sent to him by fans. Most of them were letters with baseball cards. Lowe not only signed all the cards and placed them in the self-addressed stamped envelopes, he read every word of every letter that accompanied those cards.

Here are today’s lineups:

MARINERS

Ichiro Suzuki, right field

Chone Figgins, second base

Milton Bradley, left field

Ken Griffey Jr., DH

Jose Lopez, third base

Casey Kotchman, first base

Greg Halman, center field

Guillermo Quiroz, catcher

Jack Wilson, shortstop

Left-hander Luke French, starting pitcher