(Reuters) -U.S. stock index futures slipped early on Tuesday, as investors awaited a crucial labor market report and weighed the potential risk of a government shutdown on key economic data releases.

Investor sentiment has shifted back toward risk aversion, just a day after equities posted gains. While previous shutdowns have had limited impact on markets, some analysts warned that the current episode could be more disruptive given the delicate economic backdrop.

"Shutdowns are more apt to be a temporary disruption rather than a permanent drag where the short-term economic impacts are often recouped over time," said Jack Janasiewicz, lead portfolio strategist at Natixis Investment Managers.

"However, the length of any shutdown can impact the collection and release of important economic data, especially at a time when the economy is at a crucial juncture with regards to growth and inflation."

At 05:07 a.m., Dow E-minis were down 104 points, or 0.22%, U.S. S&P 500 E-minis were down 11.25 points, or 0.17%, and Nasdaq 100 E-minis were down 39 points, or 0.16%.

The Federal Reserve's data-dependent stance has heightened the importance of incoming releases, with investors hoping for a steady stream of benign readings to keep rate-cut expectations alive and support the equity rally.

With the risk of delayed data looming over markets, the economic reports due on Tuesday, including the Labor Department's Job Openings and Labor Turnover Survey for August and the Conference Board's consumer confidence index, could carry added significance and attract heightened scrutiny.

Traders will also look to a busy slate of Fed speakers for direction, including Vice Chair Philip Jefferson, Boston Fed's Susan Collins, Chicago Fed's Austan Goolsbee and Dallas Fed's Lorie Logan.

Equities have held up well through the third quarter, with the benchmark S&P 500, the tech-heavy Nasdaq and the blue-chip Dow Jones Industrial Average all set to notch gains for a second straight quarter.

Markets will now enter the fourth quarter, historically a favorable stretch for equities due to year-end positioning and holiday spending.

Earnings commentary will start to take center-stage during the period, especially as several companies indicated plans to raise prices, a move that could have implications for inflation and, by extension, the Fed's policy path.

Nike is scheduled to report earnings after markets close on Tuesday, offering an early look at consumer demand and margin trends. Its shares were up marginally in premarket trading.

Chipmaker Wolfspeed surged 49% a day after exiting bankruptcy. Firefly Aerospace dropped 10.7% after a testing mishap destroyed the core booster for its centerpiece Alpha rocket.