We correctly defended preflop and extracted value with top pair before rivering a straight to snap-call a lead.
Checking is the standard play here. After SB checks, we have a high-equity top pair that doesn't need much protection on this dry board, making it a great candidate to check back and protect our range.
Note: Betting top pair here is slightly thin; checking back allows us to realize equity and keep Villain's bluffs in.
Once SB checks again, we should continue betting for value. While the solver prefers a massive overbet to polarize, our medium sizing still targets Jx and middle pairs effectively.
The river is a dream card. We improve to a King-high straight and SB leads into us for over half the pot. This is a mandatory call, though raising is also a strong option.