NEW YORK (CNNMoney.com) -- A weak employment report put stocks on a course to open even lower Friday after it revealed a slower than expected increase in payrolls, ruining chances for stocks to extend their recent rally.

Stock futures, which are an indication of where stocks are likely to open, fell further early Friday, following the premarket jobs report.

The Labor Department reported that the U.S. added 51,000 jobs in September, sharply lower than August's 128,000, while the unemployment rate fell to 4.6 percent.

Economists surveyed by Briefing.com forecasted employers would add 120,000 jobs to payrolls, down from the 128,000 gain seen in August. The unemployment rate was expected to stay at 4.7 percent level seen in August.

John Silvia, chief economist for Wachovia, said prior to the release of the report that a weaker than expected jobs number would raise worries about the slower economy. He said it would take payroll growth close to the current forecast, probably in the range of 100,000 to 140,000, to find the sweet spot needed for another stocks rally.

"It's a pretty narrow window, but we're priced for perfection right now," he said. "The equities expecting both moderate economic growth and Fed [rate cuts]. Any deviation from that can cause problems."

Treasurys were down following the report, leaving the yield on the 10-year note at the 4.6 percent level seen late Thursday.

Oil was lower in early trading, dropping below the $60-a-barrel level. U.S. light crude was down 11 cents to $59.67 a barrel in electronic trading, while Brent crude trading in London is 23 cents lower at $59.77.

Stocks in Asia closed little changed Friday as investors there awaited the U.S. jobs report. Stocks in Europe were mixed in early trading ahead of the report, while the dollar was lower against the euro but higher against the yen in early trading.

In corporate news, software provider Oracle (Charts) intends to keep up its quick pace of acquisition, according to Vishal Bhagwati, an Oracle vice president whose responsibilities include global mergers and acquisitions. Bhagwati made his comment to wire service Reuters Thursday after the market close. Shares of Oracle were up nearly 1 percent in Frankfurt trading early Friday.

Published reports say interest in an alliance with Nissan (Charts) and Renault has cooled at Ford Motor (Charts). Ford Chairman Bill Ford Jr. had expressed interest in alliances earlier this year while Nissan-Renault held talks about a possible alliance with General Motors (Charts). Those talks ended Wednesday.

Carlos Ghosn, the CEO of Nissan and Renault, has made clear he is looking for a North American partner. Ford named Boeing veteran Alan Mulally as its new CEO and announced a new plan to cut costs through plant closings and staff cuts, and the company is not as interested in starting alliance talks now, according to the reports.

Crown Castle International (Charts), a leading wireless tower owner, announced Friday it would buy competitor Global Signal (Charts) for $3.9 billion in cash and stock, paying $55.95 a share, which is a premium of 11.6 percent over Global Signal's closing price. Including debt, the deal is valued at $5.8 billion.

Jobs report: what's in store

More news and information on markets ahead of the U.S. open