What: Shares of specialty sporting goods retailer Finish Line (FINL) fell 20% on Friday, crushed by disappointing sales figures in the second quarter. The stock plunged to multiyear lows, reaching price levels not seen since the summer of 2013.

So what: For the second quarter, analysts had hoped to see earnings of roughly $0.57 per share on something like $491 million in top-line sales. Finish Line met the consensus earnings target but fell far short of revenue estimates. Sales increased just 3.5% year over year to land at $483 million, based on 1.5% higher comparable-store sales while analysts had expected more than double that organic growth rate.

Now what: Finish Line CEO Glenn Lyon underscored the healthy bottom-line result in spite of unsteady sales growth. "With our new supply chain system now live, we have accomplished a critical milestone which elevates our customer service levels even higher while driving efficiencies throughout our organization," Lyons said in a prepared press statement.

Kicking that efficiency into high gear is essential for the upcoming holiday season. Finish Line is struggling to find buyers for men's running shoes, partly due to not having hot new models on store shelves quickly enough. That gives competitors an edge, and Finish Line can't afford to lag behind in November and December.

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Lyons understands this, of course, and is putting up his fighting dukes. "Right now, it's put up or shut up," he said on a call with analysts.

It's not exactly "do or die," since Finish Line still boasts a fundamentally healthy and pleasantly debt-free balance sheet. The company will survive a soft holiday season, and might even weather a downright disastrous one. Many a debt-ridden retailer hasn't had that kind of luxury, and gone belly up after a single holiday calamity.

That being said, Finish Line and Lyons will obviously be much better off if the new supply chain system comes up aces this holiday. Investors want to see a repeat of the fantastic holiday sales performances Finish Line pulled off in 2009 and 2011, not the disappointing growth figures it showed for the fourth quarters of 2010 and 2012.