No doubt when Sprint-Nextel Corp. (NYSE: S), the No. 3 U.S. telecommunications company, reports third-quarter results Thursday, it will report another loss. After all, it hasn’t reported a profitable quarter since 2010.

But now the 113-year-old carrier appears to have found a Japanese partner, SoftBank Corp. (Tokyo: 9984), Japan’s No. 3 mobile carrier as well as a leading content provider, which wants to acquire a 70 percent stake. The questions are how many subscribers it will report, how many smartphones it sold and prospects for the next quarter.

The Overland Park, Kan., carrier follows bigger rivals AT&T Inc. (NYSE: T), the No. 1 telecommunications carrier, and the Verizon Wireless unit of Verizon Communications (NYSE: VZ), the No. 2 U.S. carrier, in the earnings parade. Both have reported decent third-quarter earnings gains as well as boosts in subscribers.

Sprint’s wireless unit in the second quarter had about 56 million subscribers, placing it a distinct third behind AT&T Wireless, with 105.9 million subscribers, and Verizon Wireless, with 95.9 million subscribers as of Sept. 30. Britain’s Vodafone (NYSE: VOD) owns 40 percent of Verizon Wireless.

A year ago, Sprint became the last of the Big Three carriers to offer the iPhone 4S from Apple (Nasdaq: AAPL), the world's most valuable technology company, and last quarter added the new iPhone 5. To do it, CEO Dan Hesse had to pay Apple around $25 billion in product guarantees, so that new subscribers would get the phones for less than the retail price.

The move was a success: In the first half of 2012, Sprint sold 3 million iPhones, with about 40 percent to new customers attracted to its long-term evolution (LTE) network, which rivals that of Verizon Wireless and may be better than AT&T’s.

Analysts surveyed by Thomson Reuters expect Sprint to report a net loss of $1.38 billion, or 43 cents a share, quadruple the prior-year loss of $301 million, or 10 cents a share, as revenue increases about 6 percent to $8.86 billion.

Before payments of interest, taxes, depreciation and amortization, though, the expectation is for operating profit of $1.08 billion, about 23 percent below the year-earlier amount.

Help is already on the way. This week, in the first part of the SoftBank deal, Sprint got $3.1 billion in cash by issuing bonds convertible into common shares at $5.75 each to its Japanese partner. Later, SoftBank plans to buy $17.5 billion worth of Sprint shares and return $12 billion to current shareholders and inject another $8 billion in new capital to acquire its 70 percent share, pending regulatory approval.

Analysts generally approve and lawyers say that because SoftBank is Japanese, not Chinese, it’s likely to win approval from the U.S. Justice Department, Federal Communications Commission and the Committee on Foreign Investment in the U.S.

“I would guess the lawyers already greased the skids at the FCC,” said veteran communications lawyer Walter G.D. Reed of Edwards Wildman in Providence, R.I., who’s not involved in the deal. While he expects AT&T to grumble, the only likely issue to consider is whether or not SoftBank as a foreign entity should be allowed to own key parts of the U.S. spectrum.

Indeed, Sprint has already moved to acquire more spectrum by acquiring majority control of Clearwire (Nasdaq: CLWR), the Bellevue, Wash., high-speed network founded by mobile pioneer Craig McCaw, whose mobile network was acquired by AT&T. Sprint’s likely to buy out minor shareholders Intel (Nasdaq: INTC), the No. 1 chipmaker, and Comcast Corp. (Nasdaq: CMCSA), the No. 1 cable company.

Sprint’s tottering finances are largely the result of its $33.8 billion acquisition of Nextel Corp. in 2006, which was a disaster. The enlarged Sprint hasn’t reported an annual profit since 2008.

Analysts, such as James Moorman of Standard & Poor’s, regard Sprint as a “buy” because of the SoftBank bid as well as the prospect that the company may start increasing fees for extra services, especially data plans used by smartphone customers. Sprint has a $100 monthly unlimited plan that includes a $10 charge for smartphones.

Moorman’s price target is $7.50 in 12 months.

Sprint shares fell 3 cents in late Wednesday trading to $5.62. They’ve gained 140 percent this year and doubled in price over the past 52 weeks, valuing the company at $16.8 billion.