Tuesday was a down day for the stock market, with modest losses of as much as half a percent for major benchmarks. Yet what made the session remarkable was that stocks had a major reversal from large gains early that sent the Dow briefly above the 26,000 mark and other indexes further into record territory. Now, investors are bracing to see whether the old advice of buying on dips will hold true, or if today's rise and fall might turn into a more lasting correction. Certainly, some individual stocks dropped much more sharply under company-specific pressure. Under Armour (UA 1.39%) (UAA 0.74%), Avis Budget Group (CAR 0.43%), and comScore (SCOR 1.87%) were among the worst performers on the day. Here's why they did so poorly.

Under Armour looks vulnerable

Class A shares of Under Armour finished down nearly 9% after a pair of analyst companies questioned the athletic apparel and footwear company's ability to rebound from a terrible 2017. Analysts at Macquarie downgraded the stock from neutral to underperform, with an $8-per-share price target that implies further possible declines of more than 30% due to expectations for lower earnings and balance-sheet health concerns. Meanwhile, Susquehanna was also among those negative on Under Armour, discussing in an interview that decisions to broaden its retail distribution appear to have backfired. Until the company can regain past momentum in its fundamental business, shareholders are likely to keep seeing the stock struggle.

Multiple CGI images of Steph Curry dribbling and wearing Under Armour gear.

Image source: Under Armour.

Avis tries harder but still fails

Avis Budget Group stock fell 13.5% in the wake of the company issuing preliminary figures for its 2017 financials. The car rental giant said that it expects to post full-year revenue of $8.85 billion, producing adjusted pre-tax income of $340 million to $350 million. Yet Avis warned that 2018 would see continued difficulties for the business, including higher interest rates, and cost-cutting efforts would likely only partially offset the downward pressure from those challenges. Shareholders also reacted negatively to Avis' adoption of a poison pill to defend against an activist shareholder with a large position in the stock, and they want to see the rental car specialist mount a turnaround in its business before they'll be all that comfortable with their positions.

comScore tells a story

Finally, shares of comScore took a 16% hit. The metrics provider said that it had reached financing arrangements with institutional investor Starboard Value, issuing four-year convertible notes in exchange for cash and comScore common stock and giving Starboard the option for further capital infusions at its election. comScore also reported preliminary financial data covering the past couple of years, saying that it has made substantial progress in auditing its financials going all the way back to 2015. After years of uncertainty, the fact that shareholders aren't responding positively to news that a seemingly endless accounting review is finally nearing an end doesn't bode well for comScore's long-term prospects as an investment.