Sounds like a dry fly couldn't hurt-- did you see any sign of bugs on the surface or in the air, or birds like swallows diving around picking insects out of the air? This time of year sometimes you'll birds swooping around at tree top level picking off mayfly spinners.
For smallmouth some general dry flies that might be good to have: size 10 or 12 bushy durable hairwing flies like Wulffs or Humpies, Stimulators, and foam or deer hair grasshopper patterns. These are funn to fish and would be a good choices to throw if they're not responding to your poppers and sneaky petes.
But depending where you are, and the water you fish fish, you may have some specific "Big Deal" hatches that may be going on now. If so, they're worth imitating with more specific patterns. In the East and Midwest, these summer hatches generally happen around dusk and into the evening and can drive smallmouth (and trout) nuts when they occur.
White fly - a white mayfly that hatches around dusk and into the evening often in huge numbers (White Wulff size 12 or 14)
Hex- This is a huge mayfly, with a many popular imitations, deer hair extended body, or 3xl size 6-8. Spinners can be active way after dark, so bring a flashlight and tie on a heavy leader.
Light Cahills and Pale Evening Duns there are a variety of summer mayflies with light creamy yellow body light cream or pale gray wings. Light Cahills, Pale Evening Duns or any similar shade dries like a creamy yellow body with a bleached deer hair wing Comparadun or Sparkle Dun size 12 or 14.
Hellgrammites (larvae) turn into Dobson Flies (adults) Woolly buggers for the larvae and 3" long Stimulators or foam creations for the adults.
Hope this helps.
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