CSS nth-child(odd) not working in table

Question

my situation

<table>
  <tr>
    <td><span class="test">a</span></td>
  </tr>
  <tr>
   <td><span class="test">a</span></td>
  </tr><tr>
    <td><span class="test">a</span></td>
  </tr>
  <tr>
   <td><span class="test">a</span></td>
  </tr>
<table>

I try use this in CSS

table tr td span:nth-child(odd) {
    color: red;
}

But not working... any ideas? I need only span change color