Celtics Notebook: James Young in battle for his NBA life

Credit: AP photoWALTHAM — There is much talk about competition at the Celtics’ training camp — and there will be more in the paragraphs below. But while most players are looking to solidify or even increase their role, James Young is fighting for his NBA life.

And just three days into camp, he appears to be stating his case.

At 21 years, 45 days, he is younger than any player in camp this side of rookie Jaylen Brown, who turns 20 next month. But Young is entering his third NBA season, and there is a question whether he will make it as a Celtic. The club must decide by Oct. 31 whether to pick up his $2.3 million option for 2017-18, but the more immediate issue is whether he makes the 15-man…