Sprint Nextel Corp., the country’s third largest wireless carrier, on Thursday said it lost $1.3 billion in its fourth quarter, about the same as a year ago, as it revamped its network for a comeback versus bigger competitors.

The company’s focus, and that of its investors, is on its long-term turnaround efforts rather than on short-term results. Sprint is selling 70 percent of itself to Japanese carrier Softbank Corp. for $20 billion. That deal is expected to close this summer, and provide long-ailing Sprint with a much-needed infusion of capital.