U.S. Hot List: Lee Nguyen makes Copa America case: Jozy Altidore struggling

With U.S. coach Jurgen Klinsmann set to submit his 23-man squad for next month's Copa America Centenario this Friday, the final Hot List of the 2015-16 season has arrived. Who is trending up (or down) this week? Take a look below.

Warming up

Steve Birnbaum, D, D.C. United (MLS)

Why he's here: The steady center back has helped D.C. United record an impressive defensive record this season; only six of MLS's 20 teams have conceded fewer goals.

What this means: The easy-going Californian doesn't get much press, but his form for D.C. United, combined with his solid performances for the U.S. this year, have all but ensured that his name will be on the roster when it is made public Saturday.

Mix Diskerud, M, New York City (MLS)

Why he's here: After being an unused sub in New York City FC's midweek win in D.C., Diskerud made his first start in a month in Sunday's victory in Portland.

What this means: It's certainly a welcome development for Diskerud, even though he didn't make a huge impact on the match. Still, it's probably a case of too little, too late for him to crack the Copa roster.

Tim Howard, G, Everton (England)

Why he's here: In his 414th and final game with the Toffees, Howard kept a clean sheet in Sunday's 3-0 win against Norwich.

What this means: The late-season action could give Howard an edge over idle Brad Guzan ahead of the tournament.

Emerson Hyndman, M, Fulham (England)

Why he's here: The tricky and technical midfielder, who will leave Craven Cottage when his contract expires next month, was a late cut from Klinsmann's 40-man preliminary roster, but could earn his second cap in Sunday's friendly in Puerto Rico.

What this means: As a free transfer, Hyndman is attractive to wealthy clubs; he's been linked to Celtic, Manchester United, Milan, Borussia Dortmund and others. However, the potential for regular playing time will likely dictate where he ends up, according to a source with knowledge of the 20-year-old's thinking.

Lee Nguyen, M, New England Revolution (MLS)

Why he's here: The crafty 29-year-old scored a golazo in the Revs' last match, a 2-0 win against the hapless Chicago Fire.

What this means: It can't hurt his chances, but they remain slim: only one of Nguyen, Diskerud and Darlington Nagbe are likely to make the Copa squad, with the Portland Timbers' Nagbe the front-runner.

Bobby Wood, F, Union Berlin (Germany)

Why he's here: After scoring 17 goals for second-tier Union this season, Wood signed a four-year contract with Bundesliga side Hamburg on Sunday. And he could be thrust into a starting role for the U.S. next month after a hamstring injury ruled Jozy Altidore out of the Copa.

What this means: Germany's top tier will be a significant step up in competition for Wood, but the Hawaiian-born striker's growth during the past year suggests he's ready for the challenge. Arriving on the heels of a successful summer with the U.S. would help.

DeAndre Yedlin, D, Sunderland (England)

Why he's here: In his first full season in Europe, Yedlin, on loan from Tottenham, helped the Black Cats avoid relegation from the Premier League with last week's win against Everton.

What this means: The 22-year-old's drastically improved defensive play at right back was one of the reasons Sunderland stayed up. It also makes him the odds-on favorite to man the position for the U.S. this June.

Cooling down

Jozy Altidore, F, Toronto FC (MLS)

Why he's here: Altidore will miss the Copa because of yet another hamstring injury -- the same ailment that has prevented him from playing an entire summer tournament for the U.S. since the 2010 World Cup.

What this means: Given his history, Monday's news can't help but make one wonder if the chronic hamstring issues might prevent Altidore, who is still just 26, from playing with the national team into his 30s.

Ventura Alvarado, D, Club America (Mexico)

Why he's here: Alvarado has missed three straight games since making two starts at the end of April, and he didn't make the bench for Sunday's playoff win versus archrival Guadalajara.

What this means: The lack of consistent playing time this season will probably keep the Phoenix native home this summer.

Brad Guzan, G, Aston Villa (England)

Why he's here: The 31-year-old was an unused substitute in 10 of Villa's final 19 games, including three straight to end the campaign.

What this means: It's a bad way to end a bad season for Guzan, who arrives at U.S. training camp in Miami having not played since April 23.

Matt Miazga, D, Chelsea (England)

Why he's here: The 20-year-old center back did not make the bench for Chelsea's past four games -- including two matches last week -- even though the club had little but pride to play for.

What this means: It's difficult to see Miazga making Klinsmann's Copa roster, and harder still to see him realistically competing for regular playing time under new Blues boss Antonio Conte next season. Look for him to go on loan like Yedlin did in 2015-16.