Google (Nasdaq: GOOG)'s third-quarter earnings missed forecasts, and it looks like Motorola Mobility LLC is to blame.

Google's earnings call on Thursday afternoon wasn't finished as of this writing, but it wasn't hard to see the effects of Motorola Mobility, which had its earnings combined with Google for the first time.

The "problems seem related to Motorola, where actual revenue of $2.58 billion missed our $3.25 billion estimate. Google core search seems healthy," wrote analyst Brian Pitz of Jefferies & Co. Inc. , in a note issued shortly after Google's earnings were released.

Analyst Youssef Squali of Cantor Fitzgerald had more modest expectations for Motorola -- revenues of $2.87 billion -- but that still counts as a miss.

Google stock is down 8 percent in late-afternoon trading.

Overall, Google reported revenues of $11.33 billion and net income of for the third quarter of $2.18 billion, or $6.53 per share, compared to $2.73 billion, or $8.33 per share in the 2011 quarter.

Analysts surveyed by Thomson Reuters had expected Google to make $10.65 per share on revenue of $11.86 billion for the third quarter. — Craig Matsumoto, Managing Editor, Light Reading