Updated Dec 6, 2011 1:56 PM ET  Chelsea faces a defining test on Tuesday with what is effectively a win or go home game against Valencia in the Champions League.  Every Champions League game is brought to you live in HD this season across the FOX family of networks and DirecTV, with real-time in-game coverage on Twitter @FoxSoccerTrax and @FoxSoccerTrax2 and on-line at FoxSoccer.com.  The match is arguably the most critical one the final group stage round in Europe’s richest tournament. A loss for Chelsea here would underline the decay that has hit one of England’s biggest teams and cast the immediate future of manager Andre Villas-Boas into serious doubt. Chelsea’s never exited the Champions League before Christmas.  All eight of Tuesday's UEFA Champions League matches will be available live on FOX's family of networks, FOXSoccer.tv and DirecTV.  HOME | SCORES | SCHEDULE | STANDINGS  Despite a morale-boosting win over Newcastle on the weekend, it’s hard not to escape the feeling that this is a Chelsea side in deep, deep trouble. Their new, expensive manager Villas-Boas has a pedigree right enough, but he seems to lack experience. Several key players have failed to produce this season and the newest imports have had a decidedly mixed record. Two players once considered critical — Alex and Nicolas Anelka — have been quarantined and will be shipped out come January. And the locker room, which seems to have absorbed a few too many off-the-field hits, is in an uproar.  Villas-Boas may understand the precipice on which he stands, noting in his pre-game conference Monday that the club has only itself to blame for its position. But he remained stubborn about other matters, claiming that Chelsea “always take initiative” and “will not change the way [they] play.”  Really? Chelsea’s been visibly adrift and tentative in play over the last month, with just four wins in their last ten games. They have been poor in possession, toothless up top and very vulnerable at the back. And Villas-Boas is hardly blameless.  The new manager has rarely played effective tactical football and been slow to react to on field developments. There is a sense that the Villas-Boas hasn’t yet obtained a firm grasp on his personnel nor the basics. So, it’s somewhat laughable that he insisted Monday that his club played “quality possession football.”  The question is not how things came to this, but rather, why no one expected it in the first place. Perhaps we were all blinded by the seemingly limitless wealth that owner Roman Abramovich has used to make Chelsea a European perennial and three-time Premiership winner.  When David Luiz, Juan Mata and Fernando Torres were brought in, it seemed like a reload for what was an aging, but certainly capable side. Instead, it has proven to be a classic case of misappropriation of funds. Torres’ troubles are so known that piling on here would be uncivilized; David Luiz is talented but unreliable; and the old guard of John Terry, John Obi Mikel, Frank Lampard and Ashley Cole has not impressed. Mata is the lone exception; he’s been tremendous so far.  Want your rumors distilled? Check out the top ten rumors in the soccer world with  Obi Mikel finally paid the price for his poor play, with the callow but steadier Oriol Romeu finally called upon. Nonetheless, there’s been little relief in other areas. Raul Meireles has been steady, but hardly spectacular in midfield and Terry’s limits and slow step have been viciously exploited. It hasn’t helped that “Mr. Chelsea” managed to get himself involved in yet another nasty controversy —a police investigation over alleged racial abuse of Anton Ferdinand. One has to wonder if people in the Stamford Bridge dressing room are simply getting tired of some of the antics of entitlement.  But back to the Champions League game. Valencia will miss the valued Ever Banega (knee), but have demonstrated an ability to open games up behind Roberto Soldado and Jonas, ‘Los Che’ are demonstrably better at home in Europe than on the road. Their match at Leverkusen — a 1-0 win which they managed to transform into a 2-1 loss in the span of four minutes — should be a lesson for Chelsea.  Bayer stunned the Spaniards behind the physical and aggressive play of Andres Schurrle, who announced his intent by taking an immediate booking when he came on as a sub. Schurrle used his speed to create space and score, virtually opening up the game for the Bundesliga side.  Physical is something the Blues can do, and that is exactly the kind of game they must hope to utilize against the Spaniards. What they don’t want to do is to watch Luiz conned into making a rash tackle or seeing Terry isolated. And what they must do is turn the service from Juan Mata into concrete results up top.  The nitty-gritty: Chelsea can qualify with a win or with a scoreless draw unless Bayer Leverkusen loses. They are out with a loss or a score draw.  Trecker picks: Valencia nicks a score draw. This is the match where Chelsea hits the skids.  Here’s a look at the other matches of the day in brief:  Leverkusen have already qualified from Group E, while Genk is already out, making this Group E match a dead rubber. The live game, as noted above, is a straight shot between Chelsea and Valencia.  Group F is the most complex. Arsenal’s already in, but their game against Olympiacos is a must-win-and-hope for the Greeks. The home team can advance if they beat the Gunners and if Borussia Dortmund can defeat Marseille. Marseille can advance with a win in Germany or a draw, as long as the Greeks do not win.  There are a couple other complex scenarios where the Greeks can draw and advance, and an even more far-fetched one where Dortmund can advance by outscoring Marseille by a minimum of four or five goals; as long as the Greeks do not win. A more thorough explanation will require the use of a slide rule. Do you have a slide rule?  In Group G, APOEL are in and the only thing they are playing for is top of the group against an already-eliminated Shakhtar side. Porto must win against Zenit to advance, while the Russians can go through with a draw. The match in Portugal is hard to call because Zenit has the attacking quality to take the match to the home side, but Porto has Hulk, a player well-known for dramatic results.  Barcelona’s conquered Group H and AC Milan are second. Plzen are virtually assured of the Europa League slot unless BATE Borisov can miraculously beat Barcelona in the final game. If that’s the case, I have a Nigerian prince fallen on hard times that I’d like you to meet.  Jamie Trecker is a senior writer for FOXSoccer.com covering the UEFA Champions League and the Barclays Premier League.
Jamie Trecker previews Tuesdays last matchday, as Chelsea and Valencia look to secure a place in UEFAs Champions League knockout stage. Dortmund, Marseille, Genk, Bayer, APOEL Nicosia, Shaktar Donetsk, Barcelona, BATE, Olympiacos, Arsenal, Porto, Zenit, Viktoria Plzen, and AC Milan. UCL, Chelseas season rides on the line Tuesday night vs. Valencia