<p>Arsenal defender David Luiz faces a spell on the sidelines because of a knee injury that may require surgery, manager Mikel Arteta said.</p>.<p>The 33-year-old Brazilian played all 90 minutes of a 3-3 draw with West Ham United before the international break, but missed Saturday's 3-0 home defeat by Liverpool after discomfort in his right knee.</p>.<p>"There are a few possibilities - being a little bit more conservative on the treatment, or having to go through surgery," Arteta said.</p>.<p><strong>Read more: <a href="https://www.deccanherald.com/sports/football/mikel-arteta-in-shock-as-liverpool-thumps-arsenal-970099.html" target="_blank">Mikel Arteta in shock as Liverpool thumps Arsenal </a></strong></p>.<p>"We are talking with the doctors right now to make the right decision on that, but looks like he will be out for a few weeks at least.</p>.<p>"It depends on what decision we will take. If it's more conservative it will be short-term, if it's a little bit more radical what he needs, obviously it will take longer."</p>.<p>Luiz, who is in the final year of his Arsenal contract, has made 29 appearances in all competitions this season.</p>.<p>Arteta also said full back Kieran Tierney, who was forced off with a knee problem just before half-time against the Premier League champions, is a doubt for the first leg of the Europa League quarter-final against Slavia Prague on Thursday.</p>.<p>"He felt something in his knee and he was in pain so it looks like he will be injured, but we don't know for how long," the Spanish coach added.</p>
<p>Arsenal defender David Luiz faces a spell on the sidelines because of a knee injury that may require surgery, manager Mikel Arteta said.</p>.<p>The 33-year-old Brazilian played all 90 minutes of a 3-3 draw with West Ham United before the international break, but missed Saturday's 3-0 home defeat by Liverpool after discomfort in his right knee.</p>.<p>"There are a few possibilities - being a little bit more conservative on the treatment, or having to go through surgery," Arteta said.</p>.<p><strong>Read more: <a href="https://www.deccanherald.com/sports/football/mikel-arteta-in-shock-as-liverpool-thumps-arsenal-970099.html" target="_blank">Mikel Arteta in shock as Liverpool thumps Arsenal </a></strong></p>.<p>"We are talking with the doctors right now to make the right decision on that, but looks like he will be out for a few weeks at least.</p>.<p>"It depends on what decision we will take. If it's more conservative it will be short-term, if it's a little bit more radical what he needs, obviously it will take longer."</p>.<p>Luiz, who is in the final year of his Arsenal contract, has made 29 appearances in all competitions this season.</p>.<p>Arteta also said full back Kieran Tierney, who was forced off with a knee problem just before half-time against the Premier League champions, is a doubt for the first leg of the Europa League quarter-final against Slavia Prague on Thursday.</p>.<p>"He felt something in his knee and he was in pain so it looks like he will be injured, but we don't know for how long," the Spanish coach added.</p>