I would not recommend a green sportcoat. Instead, I'd look into one or more of the following:
Charcoal herringbone sportcoat
Brown herringbone sportcoat
Brown corduroy sportcoat
Navy blue blazer
Of those four, I'd give preference to navy>>>>charcoal>>>>>>>>>>brown herringbone>brown corduroy. It's possible, I suppose, that your work/lifestyle might make grey or brown the better choice, but if you're only going to own one sportscoat navy will be the most versatile color. Green is for sportscoat #10, if that.
Is this your first one? If so, it should be grey or navy. That will work with pretty much everything every season.
If you just need fall and winter, do you have a grey or navy sportcoat? If not, get one of those. If you do, then you can move on to the browns or charcoals or green. But I really don't think green will be that versatile. It won't go with navy (IMO, anyway). It might go with rust, but it might not, depending on the two shades.