The league's marquee players have experienced different fortunes in Henry's three previous all-star appearances.
"Hopefully we can try to perform but it's not always easy," the stylish New York Red Bulls star forward said before practice Tuesday. "I remember we had a good game against Chelsea (a 3-2 win in 2012), horrible one against United (a 4-0 loss to Manchester United in 2011) and we didn't touch the ball too much against Roma the last one (a 3-1 loss in 2013)."
One day before the game, the all-star roster was still being tinkered with as Portland Timbers defender Liam Ridgewell stepped in for injured Real Salt Lake midfielder Kyle Beckerman.
Asked what you can do to get on the same page in two or three days, Red Bulls strike partner Bradley Wright-Phillips said: "There's not much."
"Everyone here can play football," added the English forward, who leads MLS with 18 goals this season. "We've just got to make it work on the pitch."
Bayern Munich is in pre-season mode so also is nowhere near the finished product, especially with World Cup stars trickling back to the lineup. But charismatic manager Pep Guardiola leaves nothing to chance and his roster is stacked with global talent.
"Well, right now they're the best team in the world," said Wright-Phillips. "They're just quality players. They're going to be very organized and it's going to be a good test for the MLS."
Toronto FC midfielder Michael Bradley was on the other side of the pitch last year with Roma. The American international knows the outcome of such games is tricky.
"Unfortunately if you win and play well, it probably doesn't matter very much and if you lose, it probably matters a little more. So the challenge for us is still to enjoy the week and enjoy the festivities but still make sure that when it's time to step on the field, we do so in a way where we're able to play well."
Said Henry: "It's going to be a hell of a challenge for us to contain that team and try to win the game, especially with the amount of time we have to put a team together."
All-stars coach Caleb Porter has said he will probably field a different lineup each half.
Like Porter, Australian midfielder Tim Cahill of the Red Bulls marvelled at the pace of simple drills at the all-stars' first practice Monday.
Both teams held open practices under bright sunshine at Providence Park on Tuesday.
The all-stars have 96 goals between them in MLS play this season, drawing talent from Canada (Portland midfielder Will Johnson), Argentina, Australia, Cuba, England, France, Mexico, Nigeria and the U.S.
Their collective salaries in 2014 are in excess of US$30 million — this in a league where the designated player rule helps inflate the allowed salary cap of US$3.1 million per club.
The all-star wages total would have been considerably higher had Los Angeles forward Robbie Keane (US$4.5 million) and Toronto FC striker Jerome Defoe (US$6.18 million) been able to attend.
Of course, nobody on Bayern Munich is going hungry either.
Off the field, the all-star game is already a win-win proposition for MLS.
Portland loves its soccer and signs of the all-star game are everywhere. The giant ad on the wall behind one of Providence Park's goals reads: "5-time European champs. 20-plus World Cup stars. 1 all star-game. Here."
And the 19-year-old North American league loves rubbing shoulders with soccer's elite like Bayern. Having Germany win the World Cup was a bonus, elevating the stature of Bayern's American tour.
For the league, the all-star game is a chance to show off how its talent level continues to grow, with marquee imports surrounded by strong U.S. talent.
Sporting Kansas City forward Dom Dwyer, tied for No. 2 on the league scoring list with 14 goals, says he constantly gets queries from back home in England about the North American league.
"Absolutely. I mean they didn't know what it was a few years ago," said Dwyer. "Now they all want to get out here, want to play here and want to be involved in it."
Wright-Phillips says he too is constantly answering questions about the league.
"I get texts weekly from players in England trying to come over," he said.
So what does Dwyer tell those who ask for his take on MLS?
"Come. It's fun."
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