Raise. The worst you'd be at this time would be if he's holding 8 [img]/images/graemlins/diamond.gif[/img]-9 [img]/images/graemlins/diamond.gif[/img] in which case you have six outs. (6 [img]/images/graemlins/diamond.gif[/img] is obviously no good).

I'd assume here he's on a straight or flush draw or maybe flopped top pair. Either way, you want to build a pot here because of your pot and implied odds. If he's got a 9 (say A-9), then you're in good shape.