"The ball is in their court now" has been a recurring statement throughout the Greek crisis — one that now seems particularly appropriate as the tennis tournament in Wimbledon enters its second week. The media turned its head after Greek Prime Minister Alexis Tsipras pulled off a "no" result in the July 5 Greek referendum, the equivalent of a fizzing backhand topspin. Now the crowd is looking at the creditors to see what kind of a return they will be able manage. The "no" option commanded 60 percent of the Greek vote, and the dominant media narrative holds that this is a devastating setback for German Chancellor Angela Merkel. Now Merkel will have to be more obliging to Greece to prevent the country from exiting the eurozone and wrecking her legacy. She cannot be the chancellor who allowed the eurozone to unravel, this story goes.

And this narrative is true — to a point. Germany is the de facto leader of the creditors and the most important decision-maker and should fear a Greek eurozone exit for numerous reasons. As it stands, a nation's decision to join the eurozone is an ostensibly irreversible step. If a member opted to leave, this would of course no longer hold. The exit of one country opens an escape route for all others. Although Spain and to a lesser extent Italy have fared better in 2015 than in 2014, their gains are buoyed by a low oil price and the weak euro. Their underlying long-term weaknesses persist: high unemployment (24 percent for Spain) and high debt (132 percent of gross domestic product for Italy). Once the current glow fades, the markets could return to target these economies with a vengeance just as they did in 2012. The difference this time would be that the cohesiveness of the monetary union would have been greatly impaired by Greece's departure. This is indeed a worrying scenario and one that Merkel wishes to avoid. But this narrative does not tell the whole story.

Germany has other worries. It is just as reluctant to write off or devalue Greece's debt to avoid a eurozone exit. Its reluctance limits Merkel's room for maneuver. If, after five months of grandstanding, histrionics, referendums and inflammatory speeches, Tsipras wins his struggle, the consequences could change the very structure of Europe. Going back to the roots of the union explains why this is problematic for Berlin. When Germany signed up to join the European Monetary Union in 1992, it did so after setting stiff preconditions. West Germany had for a long time stood economically toe-to-toe with its European peers. When East Germany rejoined West Germany in 1991, there was a good chance that the united Germany would emerge as the new monetary union's economic powerhouse. The Germans were afraid of any arrangement that would enable less productive European countries to take advantage of Germany's productivity. They requested that strong fiscal rules be incorporated into the new agreement. The European Central Bank was tightly restricted to prevent its being used as a conduit for the reallocation of funds from one member to another.

The launch of the eurozone in 1999 resulted in a credit boom in the countries with a weaker credit history because they now found themselves borrowing at German rates. Their debt burdens mounted, particularly after the 2008 economic collapse. Germany found this situation acceptable as long as the borrowers repaid their debts in the end — a large proportion of the credit came from Northern Europe. Specifically in the Greek case, a bailout later transferred the exposure from private creditors (mainly banks) to various European bailout funds and the International Monetary Fund, meaning that the Greeks now owed the money directly to the other members of the eurozone. If Germany yields to Greek pressure, the eurozone could become what Berlin has always feared.

The contagion in the second scenario would be less visible than in the first. Spanish and Italian bond yields may not soar, and crisis talks might not be held. It would, however, be just as real. The first result could be seen in Spain, where Podemos — sister party to Greece's ruling Syriza — will contest general elections before the end of the year. Lately Podemos has toned down its demands for a re-evaluation of Spain's debt (97.7 percent of GDP), but a result for Syriza would surely bring the subject back to the forefront. Syriza-like parties might spring up in other countries with high debt, such as Portugal and Italy, demanding a similar deal. The precedent set by Greece would be hard to resist.

More troublesome for Merkel, this scenario would run a greater risk of undercutting her own government's popularity: The German population is extremely sensitive to any development that resembles a step toward a transfer union, which explains the deep antipathy toward Greece. The immediate political challenge might be lessened by the other piece of news from the weekend, that the anti-eurozone party Alternative for Germany has just elected a leader who feels more strongly about immigration than about economic matters. This eases some pressure. If a transfer union were to become a real danger, however, Alternative for Germany could resurge. If not, another Euroskeptic party would surely rise to take advantage of the popular tide. In short, Merkel might end up saving the eurozone but in such a way that it is no longer suitable for Germany to live in.

Thus the German government must walk a fine line. If it is harsh on Greece, yielding to pressure from the German people as well as hawkish governments of Eastern Europe and Spain, Germany (and Merkel) could go down in history for having pushed Greece out of the eurozone. On the other hand, if it listens to the more conciliatory France and Italy, or heeds the economic debt relief arguments of the IMF urging measures to make Greek debt sustainable, it runs the risk of laying the foundations for a future Europe that does not work for Germany. Faced with this dilemma, the wise move is to work out the position between the scenarios and stick to it. Such a position would be one that best suits the German line, where a deal can possibly be struck with Greece and yet German interests are not compromised.

And this is what we have seen over the past five months. Tsipras and his government have tried an array of tactics to shift the creditors' position, with the referendum being the latest one, but the creditors have refused to move. Assuming the IMF's debt relief report is not a game-changer, and that France and Italy are unwilling or unable to rock the boat enough to change Germany's position, then it is not set to move. Thus the ball would seem to still be in Tsipras' court. The problem for Tsipras in this tennis match is that he is not playing against an opponent, but merely hitting a tennis ball against a wall.