title: how to remove "(x)" from a string
body: <p>I'm working on tennis database and I would like to remove "(x)" from scores. </p>
  
  <p>For example : 
   <code>7-6(7) 6-2 --&gt; 7-6 6-2</code></p>
  
  <p>I try :</p>
  
  <pre><code>gsub("(2)","",Tennis2017_table$score) 
  </code></pre>
  
  <p>just to see if I could remove the "(2)" but it only removed all the "2"</p>
  
  <pre><code>gsub("\\(|\\)", "", Tennis2017_table$score)
  </code></pre>
  
  <p>but it only remove ()</p>
  
  <p>I've searched similar problems and try to adapt the issue to mine but it didn't work...</p>