Thursday was a strange day in the stock market. That could be good news.

Wall Street saw a dramatic shift in market direction on Thursday, with one-day gainers and losers swapping places. And that may prove to be just what the rally needs to continue.

the Russell 2000 The small-cap index, which has struggled to find its footing all year, rose more than 3% on Thursday. At the same time, all of the stocks in the so-called “Magnificent Seven” fell, including a more than 5% drop in Nvidia and a decrease of 2.3% appleresulting in a decrease in both Standard & Poor's 500 And Nasdaq Composite.

Bespoke Investment Group shared two statistics on social media site X to show how rare this type of split is.

Thursday was the second day since 1979 that the Russell 2000 rose more than 3% while the S&P 500 fell. The Nasdaq Composite underperformed the Russell 2000 by more than 5 percentage points in what appeared to be the largest daily gap ever. The only other time the gap exceeded 5 percentage points was in November 2020, right after Pfizer Inc. reported positive results from its COVID-19 vaccine trial.

While major market averages and many individual 401k accounts may be showing a decline today, this odd set of results could be a positive sign for the market. Much of the recent rally has been driven by big tech companies, prompting investment professionals to worry about a narrow group of stock market leaders.

“Today is a big day,” Ed Yardeni of Yardeni Research said on CNBC’s “Closing Bell.” “This is the day when investors start to move out of the top 7 and into the rest of the market. I don’t think this will continue to push the S&P 500 down — I think there will be enough money to keep the blue-chip stocks that have done well up somewhat, but I do think we will see more gains in the S&P 493, as well as in small- and mid-cap stocks.”

The split came after the June consumer price index report early Thursday showed that headline inflation fell last month and is now up about 3% over the past year. That has boosted confidence that the Federal Reserve will start cutting interest rates as soon as September. Fed Chairman Jerome Powell indicated in congressional testimony this week that the central bank was aware that keeping rates high for too long could hurt the economy.

“Investors are rotating: They’re jumping from large-cap tech to mid-cap and small-cap, along with real estate,” Sam Stovall, chief investment strategist at CFRA Research, told CNBC. “They’ve been waiting for maybe not a guarantee, but certainly a confirmation that the Fed is likely to start cutting rates, and not do it in response to a recession.”

Activity in the bond market supports this idea. Yields on U.S. Treasury bonds fell broadly on Thursday, suggesting that government bond prices were rising.

“We got the positive CPI on the back of Powell’s slightly dovish comments,” Ross Mayfield, investment strategist at Baird, told CNBC. “Prices have come down significantly, and you have a kind of cyclical trading. But the problem with the market being so focused on big tech is that that cyclical trading can look negative on the surface. And I think we’re seeing some of that today.”

There are also signs in recent months that the U.S. economy is starting to weaken. Slow growth or a recessionary environment would certainly pose a challenge for small-cap stocks, which tend to be more sensitive to the economy and more focused on the domestic market than larger companies.

— CNBC's Sarah Main and Alex Haring contributed reporting.