The San Diego Chargers have high expectations heading into the 2013 season, but things got a bit more difficult for the team after a big injury on offense, as wide receiver Danario Alexander tore the ACL in his knee and likely will be lost for the whole season.

According to ESPN.com, Alexander tore his anterior cruciate ligament in his right knee while working in practice on Tuesday and now he will be done for the year. Alexander is one of the top young receivers on the team and made 37 catches for 658 yards and seven touchdowns in the final nine games after being acquired during the season. Alexander was expected to be a big part of the offense and it is another weapon that won't be around for Philip Rivers.

Robert Meachem may now get more playing time, as will rookie Keenan Allen. Meachem was a mess last season and is due $5 million guaranteed and he had a rough game after dropping a potential touchdown pass in a 7-6 loss at Cleveland last season. Rivers and new head coach Mike McCoy were expecting big things from Alexander on the offense as they try and improve the passing game and now he is the latest Charger to suffer a serious injury.

Melvin Ingram was lost for the season in May and now Alexander will be gone and one big issue is the fact that he has had past knee problems and will be his sixth knee surgery since college. Alexander showed off some skills last season with 17.8 yards per catch and now names like Malcom Floyd, Vincent Brown, rookie Keenan Allen, Eddie Royal and Robert Meachem will have to step up.