In announcing that he will retire next year rather than run for a reelection for a seventh six-year term in the Senate, Republican Sen. Richard Shelby of Alabama explained: "For everything, there is a season."

Shelby's retirement "season" comes as the GOP will try to reclaim in the 2022 midterms the Senate majority it just lost in the 2020 election cycle. With the new announcement, the Senate Republicans now find themselves defending four open seats, including two in very competitive battleground states.

ALABAMA'S SHELBY ANNOUNCES HE'LL RETIRE FROM THE SENATE AFTER NEXT YEAR

Besides Shelby, GOP Sens. Richard Burr of North Carolina, Pat Toomey of Pennsylvania, and Rob Portman of Ohio are also stepping down after 2022 rather than seek another term in the Senate.

"Retirements are a natural course of events for both parties," Brian Walsh, a former NRSC communications director and former senior adviser to GOP Sen. John Cornyn of Texas, told Fox News.

And veteran GOP strategist and former Republican National Committee communications director Doug Heye said, "I think for a lot of them, it’s just time."

Pat Toomey of Pennsylvania, Richard Burr of North Carolina, Rob Portman of Ohio and Richard Shelby of Alabama are stepping down after 2022 rather than seek another term in the Senate.

Pat Toomey of Pennsylvania, Richard Burr of North Carolina, Rob Portman of Ohio and Richard Shelby of Alabama are stepping down after 2022 rather than seek another term in the Senate.

Heye noted that that for some lawmakers, it’s just "been there and done that for a long, long, time. That’s just a reality of where they are and the system of who’s up every two years in the Senate."

That seems to be the case with Shelby, who’s 86.

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And that could possibly be the case with 87-year-old GOP Sen. Chuck Grassley of Iowa, another member of the Republican old guard who’s stayed mum so far on whether he will run in 2022 for an eighth term.

Grassley told Iowa reporters last week that any decision is "several weeks off, I would say."

"Shelby is approaching 90 so there’s no surprise there. It would be a similar case with Grassley if he decides to retire," a GOP strategist who works on Senate races told Fox News.

But for Portman and Burr, who are 65, and for the 59-year old Toomey, age was likely not the deciding factor.

"Certainly Toomey and Burr stepping down is not ideal, but to be honest I don’t think either of them were ever going to serve more than two or three no matter who was in the White House and what the political environment was," noted the strategist, who asked to remain anonymous to speak more freely.

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Portman’s recent 2022 news was more of a surprise.

And his announcement came with the Republican Party out of power in the White House as well as both houses of Congress. The GOP’s at a crossroads — it will return to its conservative roots or remain the populist party reshaped and ruled over for four years by then-President Trump. The now-former president has vowed to remain extremely influential in the GOP going forward and public polling indicates Trump remains very popular among Republican voters.

Pointing to the 2022 midterms, where the GOP need to flip just one Democratic-held seat to win back the majority, Walsh highlighted that retirements are not always a bad thing.

"After President Obama took office in 2009 for example, there were 12 Senate retirements ‒ six in each party ‒ and Republicans still gained seven seats in the 2010 elections," said Walsh, a veteran of numerous Senate, congressional and gubernatorial campaigns.

But he emphasized that "candidate quality is critical though and where open seats have been problematic for Republicans in particular has been in nominating polarizing candidates like Alabama’s Roy Moore or Delaware’s Christine O’Donnell, who are unelectable in a general election. So if Republican voters want to be in a position to hold these seats and also win back the Senate in 2022, they must take care to nominate strong candidates who have broad appeal."

Another Republican Senate incumbent, two-term Sen. Ron Johnson of Wisconsin, is also mulling retirement rather than reelection in 2022.

Johnson, who was first elected to the Senate in the Tea Party wave of 2010 and who’s become a major Trump loyalist and supporter in recent years, would likely face a challenging reelection run in a fierce battleground state that President Biden narrowly flipped from red to blue last November.