LA Galaxy vs. Seattle Sounders Showdown: Who has the better backline?

The LA Galaxy and Seattle Sounders will battle it out in a home-and-home over the next two weeks to determine which team takes home this year's Supporters' Shield and the No. 1 seed in the Western Conference. It all starts with this Sunday's nationally televised match at StubHub Center (8 pm ET, ESPN2, TSN2 in Canada).
This week MLSsoccer.com's editors will take a look at the positional battles that will ultimately decide the outcome of both games. On Tuesday, we focus on the defenders.
Monday: Penedo gives the Galaxy the goalkeeping edge

Team
<strong>Analysis</strong>
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<p>It doesn&#39;t take an analytics buff to understand that one stat reigns supreme when it comes to defensive prowess. You&#39;ve got to keep the ball out of the back of the net by any means necessary, and LA&#39;s got that down pat. They lead the league with just 33 goals conceded, 15 fewer than the Sounders. It makes sense then that they&rsquo;ve faced the second fewest shots in MLS (334), too. Numbers aside, <a href="//www.mlssoccer.com/players/omar-gonzalez" target="_blank">Omar Gonzalez</a> may be the most dominant aerial presence in the league (<a href="//www.mlssoccer.com/players/chad-marshall" target="_blank">Chad Marshall</a> certainly has something to say about that), and the big man&rsquo;s long-time partnership with <a href="//www.mlssoccer.com/players/aj-delagarza" target="_blank">AJ DeLaGarza</a> is a rock solid foundation to build upon. If <a href="//www.mlssoccer.com/players/robbie-rogers" target="_blank">Robbie Rogers</a> is healthy and <a href="//www.mlssoccer.com/players/dan-gargan" target="_blank">Dan Gargan</a>&rsquo;s patrolling the right flank, this is unquestionably MLS&rsquo; best unit.</p>
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<p>There have been, ahem, a few frustrating defensive hiccups this year for the Sounders. One game they&rsquo;ll look dominant, and the next they&rsquo;ll draw 4-4. Or drop 5-0. Or 3-0. Or 4-1. You get the picture. Seattle&rsquo;s formula has been to outscore teams, which they&rsquo;ve done enough to sit tied for the Supporters&rsquo; Shield lead, but there are valid concerns about this group outside Marshall and <a href="//www.mlssoccer.com/players/deandre-yedlin" target="_blank">DeAndre Yedlin</a>. It&rsquo;s been a merry-go-round alongside Marshall between <a href="//www.mlssoccer.com/players/djimi-traore" target="_blank">Djimi Traore</a>, <a href="//www.mlssoccer.com/players/zach-scott" target="_blank">Zach Scott</a> and <a href="//www.mlssoccer.com/players/jalil-anibaba" target="_blank">Jalil Anibaba</a> and left back hasn&rsquo;t been much more consistent. The fact that these struggles came with <a href="//www.mlssoccer.com/players/osvaldo-alonso" target="_blank">Ozzie Alonso</a> camped in front speaks for itself.</p>
<h2 class="rtecenter"> Edge</h2>
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