Opening move in a race to fifty

Two players take turns adding a whole number between $1$ and $10$ (inclusive) to a running total that starts at $0$. Whoever brings the total to exactly $50$ wins. You move first. Which number should you open with to guarantee a win?

$6$. Whatever your opponent adds, you can reply so the two moves sum to $11$. So the winning totals are those congruent to $50\equiv6\pmod{11}$: $6,17,28,39,50$. Open with $6$ and keep landing on that sequence.