Los Angeles FC remain the favorites to win the MLS Is Back tournament, although at least one sportsbook lengthened their odds after reigning league MVP Carlos Vela opted out.

LAFC remained the 350 moneyline favorites at DraftKings and 500 at FanDuel on Monday, but their odds lengthened to 600 at DraftKings by Tuesday morning. However, the odds had not moved at FanDuel, where Atlanta United FC remain the second betting favorites at 750 followed by the reigning MLS champion Seattle Sounders at 800.

The five-week tournament is scheduled to begin Wednesday at the ESPN Wide World of Sports Complex near Orlando. MLS gave players the opportunity to skip the event for health or family reasons.

Vela, 31, the LAFC captain and the team's highest-paid player at $6.3 million for 2019, is the highest-profile player to opt out. He will remain home with his pregnant wife, Saioa, and the couple's 3-year-old son, Romeo.

Vela broke the MLS single-season scoring record with 34 goals in 31 games last season while leading LAFC to the Supporters' Shield. In his first season with LAFC in 2018, the Mexican international recorded 14 goals and 13 assists in 28 games (26 starts).

LAFC had one win and one tie when the MLS season was paused in March due to the coronavirus pandemic, and Vela had scored two goals.

LAFC are scheduled to open MLS is Back play in Group F against the Houston Dynamo on July 13. The other two teams in the group are the Los Angeles Galaxy and the Portland Timbers.

Tournament odds have been far more volatile at DraftKings, with the landscape further changing following the withdrawal of FC Dallas on Monday due to numerous players testing positive for COVID-19.

The Sounders were 1600 at the book last week, equal to New York City FC, Sporting KC and FC Dallas. Dallas had been in Group B along with Seattle, the Vancouver Whitecaps and San Jose Earthquakes.

By Tuesday morning, Seattle's had leaped to 700, behind only LAFC. Atlanta and NYCFC were 1100, followed by Sporting KC at 1200.

While the Sounders' odds have shortened, the Earthquakes have gone from 1800 at DraftKings last week to 4000. The Whitecaps remain the second longest shots at 8000 with forward Fredy Montero opting out of the tournament on Monday night.

Vancouver's odds are ahead of only Nashville SC (10000) at DraftKings.

"Due to the current situation with Covid-19, I made the hard decision to stay with my wife and daughters in Canada, instead of traveling with the team to Florida," Montero wrote in an Instagram post."