PP 2nd Final Board 1

♠ A J 4 2		♠ Q 9 6 3
♥ A J 5		♥ K 7 4 2
♦ 9 4		♦ K 10 6 2
♣ K Q 9 4		♣ 2

Board 1
Dlr N
Vul None

West	North	East	South
	Pass	Pass	Pass
1NT	Pass	2♣	Pass
2♠	Pass	4♠	All Pass

A 3rd/low ♥3 lead runs around to the 9 and your jack. How do you play?

	♠ K 10 8
	♥ Q 8 3
	♦ A 8 7
	♣ J 6 5 3
♠ A J 4 2		♠ Q 9 6 3
♥ A J 5		♥ K 7 4 2
♦ 9 4		♦ K 10 6 2
♣ K Q 9 4		♣ 2
	♠ 7 5
	♥ 10 9 6
	♦ Q J 5 3
	♣ A 10 8 7

I still have no idea what's right.

After winning ♥J I played a diamond to the king and a club to South's Ace. Then they played 2 more diamonds tapping me, and I was worried about losing a trump and having some trouble on the 4th diamond.  So I banked on 3-3 hearts and crossed in hearts to lose a spade finesse, then only needed one club trick to go with 4 trumps, 4 hearts, and the ♦K.

If I lost a spade hook at trick 3, they'd tap in diamonds and now I'd have to guess to ruff a diamond high and hook the ♠9 to get home.

Perhaps for this reason playing a diamond is wrong. I could see crossing in hearts to play a club, or even playing a club out of your hand to retain communication. If they push clubs you have more flexibility to retain control, plus they might not be able to ever overruff. Say you lose the first, ruff the 2nd, and hook in spades.

Note that 4th best leads would have made this hand a lot harder.

In any event, 420 was good enough for 15/17. As for bidding game, well +140 would have been 10.5 -- most common result appears to be 4♠ down 1.