CARSON, Calif. – Bruce Arena is again railing at the schedule-makers, bemoaning the LA Galaxy's CONCACAF Champions League slate on the eve of Wednesday night's clash with El Salvador's Isidro Metapán (10 pm ET, Fox Sports 2).

The Galaxy's head coach and general manager has been outspoken about MLS' schedule in the past, but on Tuesday he took a swipe at CONCACAF for what could make for a hectic next few weeks for his club.

LA have two of their most important matches of the season over the next four days – the CCL match, which could all but send them to next year's knockout stage, and Saturday's showdown with Western Conference/Supporters' Shield leaders Seattle, both at the StubHub Center – then travel next week to Costa Rica for a CCL game with Cartaginés and to Portland for a critical match in the playoff chase.

“I'll be quite honest with you,” Arena said. “Between CONCACAF and MLS, they screwed up the dates. We likely would have played this date regardless, but the dates of the [CCL] competition got changed from the way we scheduled our MLS regular season, so it makes it a little awkward.”

Arena's beef is with the rhythm of the CCL schedule. The Galaxy played just once in Group 8's first three “match days” in August – a 2-0 home victory over Cartaginés on Aug. 20 – and have games on each of the last three: Wednesday's game, the game in Costa Rica on Sept. 25 and the Oct. 24 group finale against Isidro Metapán in San Salvador.

The LA boss is most unhappy with that last date, which splits an Oct. 20 home game with California Clasico rivals San Jose and the Oct. 27 regular-season finale at Seattle, a game that could determine plenty.

“We weren't supposed to be playing in October, that's for sure,” Arena said. “That becomes a ridiculous exercise at the end of the year. We should have played the two dates in August and the two dates in September and nothing in October.”

MATCH PREVIEW: No Donovan or DeLaGarza as Galaxy return to CCL play

There were three “match days” in August, and Cartaginés and Isidro Metapán met on two of them.

Last year, when the CCL first had three-team groups and each club played on four of six match days, the Galaxy played two games in August, one in September and finished up at Metapán on Oct. 25. The Galaxy won the group stage before eventually falling in the tournament semifinals.

When MLSsoccer.com presented CONCACAF with Arena's comments, a confederation official claimed they worked with the Galaxy on their schedule in the tournament. The team's inclusion in the International Champions Cup forced CONCACAF to avoid scheduling the team a CCL game during the first "match day" from Aug. 6-8.

"CONCACAF worked in coordination with the Galaxy to build their CONCACAF Champions League schedule with the only five dates the team had available, due to their commitment to play in [the International Champions Cup friendlies] the first week of August," said the spokesman.

Still, the schedule does not hinder the Galaxy in the CCL, Arena said.

“Metapán is playing [league] games, we're playing [league] games – it's no different for us than it is for the opponent,” he said. “It makes it a little harder in the league, but that's all part of it as well.”