Joe Mauer and his wife, Maddie, are expecting twins. And they've decided to wait until the moment of birth to learn the gender of each new Mauer.

"I told him to do that," Justin Morneau said. "It's the greatest surprise ever, babies come out and you look and then you can announce it to everyone.

"There are no more surprises in life. You know what you're getting for Christmas."

While we wait for the double baby bonus in a few months, Morneau's statement about surprise carries a double meaning.

Mauer and Morneau have lived together, won MVP awards, gotten married, placed balls on tees for each other, experienced parenthood (or are about to) and become the faces of a franchise. This is their 10th season in the same lineup, but they know their bromance could become a long-distance one.

Morneau, in the final year of a six-year, $80 million contract, might not be back for 2014. The Twins have Chris Parmelee, currently the right fielder but better suited at first. If Morneau has a big season, the Twins could be persuaded to sign him to an extension. But a big season could also mean the club might decide to trade him before the July 31 deadline when his stock is high.

The Twins also could let him walk as a free agent and try to get a draft pick as compensation. If he has a poor season, they could just let him walk.

The realities of sports and business could be hard for Twins fans — as well as the M&M boys — to swallow.

"It's never easy when you have to leave anywhere you have been for a long time," Morneau said. "You develop friendships and everything. I'm not looking that far ahead."

Mauer rarely says anything controversial and would only point out that he could lobby all he wants on Morneau's behalf but doesn't have final authority. It's safe to assume the St. Paul native would let someone know his displeasure if Morneau isn't back next season.

"He's a good friend of mine. He's a great teammate," Mauer said. "He's great in the clubhouse, works hard and is a great example to a lot of the younger kids here. I would love to play with him for the rest of my career. On the other side, things happen. Everyone knows where I stand."

When the two are in the lineup together, the Twins have been a tough team to beat. But since 2005, the Twins have fielded a lineup without one or the other more than 400 times. The Twins made the playoffs in 2009 and 2010, but Morneau didn't play because of a stress fracture in his lower back in one postseason and concussion symptoms in the other. Beating the Yankees is hard with only one M boy in the lineup.

If this is their last season together, at least they enter with no ailments.

"It is very comfortable having those two lefthanded bats in the lineup," Twins General Manager Terry Ryan said.

One of the story lines of 2013 will be if Ryan and the Twins decide to keep that comfortable feeling beyond this season.

"We will certainly address it when the time comes," Ryan said. "It will take care of itself."