Galaxy star Landon Donovan is running on fumes

The face of U.S. soccer often hides behind a hat and sunglasses.

“And a fake nose,” the face adds with a smile.

Clearly anyone who believes Americans have ignored the world’s most popular sport has never gone to the mall with Landon Donovan.

“It used to bother me, before the World Cup,” Donovan says of being mobbed in public. “If I’m out just like this with no hat on or no glasses, then I have to assume that’s going to happen. But it’s part of it.”

“It” being the fallout from a spectacular World Cup in which Donovan scored three times in four matches, lifting the U.S. into the second round with a stunning extra-time goal that beat Algeria and made him a national star overnight.

But fame has its drawbacks, exhaustion being one of them. And that will add to the challenge when Donovan takes the field for the Galaxy against FC Dallas in Sunday’s Western Conference title game at the Home Depot Center.

Donovan has played 51 matches worldwide in the last 44 weeks, beginning with his debut for Everton of the English Premier League in January. And given that he has played many of those in the midfield, where he keeps up a frenetic pace, he has run an estimated 330 miles in those games — the equivalent of 13 marathons — much of it in 40- and 50-yard sprints.

Add in the long flights to England and South Africa and visits to 11 states, Puerto Rico and Canada with the Galaxy and it’s no wonder Donovan’s get-up-and-go and has got up and went.

“Unless you play in a World Cup, nobody will ever know how emotionally draining that tournament is,” Donovan says. “Most guys can’t recover from it. So it’s a difficult thing to do. I want to rest. But now I really want to challenge myself to keep getting better.”

The top scorer in Galaxy history, Donovan, 28, has seen his production fade as his energy waned — he hasn’t scored a goal in nearly two months and he has only two assists since mid-September. In the Galaxy’s playoff series with Seattle, he failed to record either a goal or assist in consecutive postseason games for the first time in his career.

Yet that has made the Galaxy a better team, Coach Bruce Arena says.

“He’s equally effective in the role he plays now,” says Arena, who has seen Edson Buddle and David Beckham pick up much of the heavy lifting on offense while Donovan has unselfishly dropped back to play defense. “He’s focused on the team. If he’s positioned to get a goal, he’ll get a goal. But that part doesn’t concern me.

“His commitment to do what needs to be done has made our team better.”

And it has made Donovan better as well. No longer is he simply a supremely talented, if somewhat cocky, offensive threat. He has become a complete player and mature leader willing to trade personal success for team goals.

“He’s changed a lot,” says Arena, who has coached the Galaxy captain since he was a teenage phenom. “He was a young brash kid. Now he’s a real mature, experienced veteran. On the field and off, it’s just a maturing of a player and a person in a good, positive way.”

At times that has led Donovan to make suggestions to the coaches, while at others he has gotten after teammates.

“He’s always pushing guys,” Buddle said. “If you’re not moving or you’re not staying active, he’s making sure you are. That’s why he’s so important to the team.”

Even when he is tired.

The night before the Galaxy’s last regular-season game, Arena called Donovan and told him he’d sit out the finale. But when Real Salt Lake rallied to tie its last game, leaving the Galaxy needing a win to clinch home-field advantage in the playoffs, Arena called back and told Donovan he had to play.

“I had a few minutes where I was literally physically sick,” Donovan remembers.

Then he went out and played 90 minutes, getting his league-leading 16th assist on the tying goal in a 2-1 victory.

“I think this has been my most complete year,” says Donovan, a three-time U.S. player of the year and former MLS scoring champion who was the league’s MVP last season. “And it doesn’t always show up on the stats. But from a leadership standpoint and from helping our team win… this year feels better.

“I just feel something special this year. And I think we’ve got a really good chance to win it.”

The Galaxy lost the MLS Cup to Real Salt Lake on penalty kicks last year, but a win over Dallas on Sunday would send it back to the title game for a chance at redemption — and a chance to prove Donovan’s hunch right.

That would also provide a fitting end to a long, exhausting year. And Donovan does mean end. Although there has been talk of him returning to England to play for Everton, Newcastle United or Liverpool, Donovan promised that will have to wait until long after the MLS season ends.

“I have told myself and everybody in my family that I’m taking at least two weeks where I don’t want to see anyone, talk to anyone, do anything,” he says. “If you ask me now I would say it would be hard to go back just because of the lack of rest.

“If for some reason I feel good after those few weeks and they want me to go somewhere, then I’ll think about it.”

kevin.baxter@latimes.com