Scoring: IMP
West North East South
1♥ Pass Pass 1♠
2♣ 4♠ Pass Pass
Pass
I played this hand on BBO. At the table, west led a trump, and continued second trump when he got in with ♦A, so i finally had only 9 tricks by cross-ruff.
Later, i find i can make the contract if the lead is ♣s, but the correct line is not easy to me.
For example, West leads ♣K, how do you play?

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