Costa Rica's Campbell could miss 6 months with knee concern

If Joel Campbell didn't have bad luck, he might not have any luck at all.

The Costa Rica star's Gold Cup is over and he could face up to six months on the sidelines after tearing a knee ligament during the early stages of Tuesday's 1-1 draw with Canada.

"It is sad and difficult to have to leave the national team," Campbell said in a statement on his personal website Friday. "I gave it everything, as I always do. Now I have to think about my recovery to come back stronger than ever."

Campbell has a year left on his deal at Arsenal following a fifth loan spell, this time with Portuguese giant Sporting, and his future's now in footballing limbo.

Though he didn't specify how long he'll be out, the forward's injury usually requires a four-to-six-month recovery period.

He's surplus to requirements at the Emirates Stadium - especially after Arsene Wenger admitted he'd stick with a back-three formation that lessens the importance of traditional strikers.

The 25-year-old made just seven league starts last season for the Lisbon side, marking a fifth temporary move after spells with Lorient, Real Betis, Olympiacos, and Villarreal followed his 2011 transfer to Arsenal.