Arsenal’s defeat to West Brom on Saturday delivered an undeniable blow to their Premier League title chances, but with 25 games left to play there remains plenty of time to make amends. A similar slip-up at home to Dinamo Zagreb on Tuesday, on the other hand, would be fatal to the Gunners’ Champions League hopes.

Ahead of Arsenal’s debut in this season’s competition in Zagreb, Wenger spoke of his burning desire to lift the one major trophy to elude him in his 19-year reign in north London. With the years of parsimony supposed to be behind them and a squad featuring such world-class talents as Alexis Sánchez and Mesut Özil, Wenger was bolder about his side’s chances than he had been in some time.

Yet, within hours, that confidence looked to be severely misplaced. Arsenal put in an insipid display in the Croatian capital to slump to a 2-1 defeat. Two weeks later matters took a further turn for the worse with a calamitous 3-2 loss at home to Olympiakos. Ever since then, Arsenal have been facing an almighty uphill struggle just to make the Champions League knockout stage.

Three points from two games with Bayern Munich was certainly respectable, even if a 5-1 loss in Germany was painful to swallow. But it still leaves Arsenal needing maximum points from their final two games -- at home to Dinamo and away at Olympiakos. Even that may well not be enough. A point for Olympiakos in Munich on Tuesday and Arsenal will be out, regardless of what happens at the Emirates Stadium. Even a defeat for Olympiakos would still mean Arsenal having to win by two clear goals or a high-scoring one-goal win in Greece. Their prospects of avoiding an exit before the last 16 for the first this century are hanging by a thread.

With such a precarious position, Arsenal’s buildup has hardly been ideal. Not only was there a 2-1 defeat to West Brom which lost Arsenal a share of the Premier League lead, but the club’s already concerning injury crisis took a further turn for the worse.

The impact of losing Francis Coquelin was already felt at the Hawthorns on Saturday, with Arsenal conceding two sloppy goals in his absence. And it has since been revealed that Wenger will have to do without the 24-year-old for at least two months. Of all the players in his squad, Coquelin may have been the one Wenger feared losing most.

Having ignored the clamor to sign an extra defensive midfielder in the summer, Arsenal’s alternatives are thin on the ground. And one of them, Mikel Arteta, also suffered an injury at the weekend. Already filling the treatment room were Jack Wilshere, Alex Oxlade-Chamberlain, Theo Walcott, Danny Welbeck, Tomas Rosicky and David Ospina. The one glimmer of light is that Aaron Ramsey is now back available for Tuesday’s encounter.

Dinamo Zagreb go into the game still with a chance of making it beyond the group stage themselves, although it is even slimmer than that of Arsenal’s. The Croatian champions would need not only to beat Arsenal, but to have Olympiakos defeat Bayern Munich and then beat the German giants themselves by at least five goals in their final match.

Like Arsenal, Dinamo’s preparations have hardly been smooth. Midfielder Arijan Ademi tested positive for a banned substance following Dinamo’s win over Arsenal in September and last week was handed a four-year ban by UEFA. Not only will he be absent at the Emirates, but Dinamo will be without the suspended defender Josip Pivaric.

Prediction: Arsenal have serious problems to overcome in the medium term, but on Tuesday those issues are unlikely to be exposed. Dinamo went into the first match between the sides on a 41-match unbeaten run, but they have lost five times since then, including a recent run of four successive losses. Arsenal should be too good.

Predicted score: Arsenal 2-0 Dinamo Zagreb

Kickoff time: 2:45 p.m. EST

TV channel: Fox Sports 1

Live stream: Fox Sports Go, Fox Soccer 2Go, ESPN3