Think of it as fantasy camp for sports memorabilia collectors. Collectors from throughout the country are reserving their seats at Yankee Stadium for the second day portion, Dec. 9, of a two-day auction organized by Grey Flannel Auctions and Yankees Steiner Collectibles.

They are coming to the House that Ruth Built to buy memorabilia – more than 200 items – that for the first time are being reconnected to the place where baseball history and heroes were made. More than 1,200 other important items will be auctioned through Dec. 8 on the Grey Flannel Auctions website, www.greyflannelauctions.com.

On Dec. 9 a total of 400 bidders will make their way to a heated tent area along the third base box seats of Yankee Stadium. Tickets are going fast and bidders are urged to call (631) 288-7800 ext. 223 to reserve their seats. Tickets are free, but are available through reservation only. Those who are unable to attend the live auction at Yankee Stadium, should call (631) 288-7800 ext. 242 to reserve a phone line.

And if the splash at Yankee Stadium isn’t enough to fulfill a fantasy baseball experience, here is also an extraordinary offering of etched induction medallions and plaques from the Naismith Basketball Hall of Fame and Museum in Springfield, Mass. The Basketball Hall of Fame is selling many of the medallions that were part of the display of the Hall of Fame building that closed in 2001. These prized artifacts became part of the Hall of Fame, beginning in 1985. In 2002, when the Hall of Fame moved into its new facility, the medallions were not retained in the new design.

Among the medallions being made available in the first 100 lots in Day 1 of the sale are those emblazoned with the images of John Wooden, Red Auerbach, Jack Ramsay, Hank Iba, Larry Bird, Kareem Abdul-Jabbar, Bob Cousy and Pete Maravich, among scores of other great Basketball Hall of Famers. The metal medallions of the full offering are of two types.

“These induction medallions are as close to a monumental piece of basketball history as one can possibly own,” said Richard Russek, president of Grey Flannel Auctions. “Aside from their historical significance, these plaques are wonderful works of art.” Internet bidding in the auction began Nov. 1 at the Grey Flannel website. Catalogs featuring the more than 1,400 items are in the mail. Internet bids will be accepted until Dec. 8, when the action shifts to Yankee Stadium. At that time, all bidding will be taken live or over the phone only. Call 631-288-7800 (ext 242) to either reserve a ticket or, if you cannot attend, to reserve a phone line. A preview of items for the live auction will take place Dec. 8 and the morning of the next day in the Great Moments Room at Yankee Stadium.

Russek said every hero from most every generation of the Yankees will be represented in this sale – items touched by Ruth, Gehrig, Dickey, DiMaggio, Mantle, Berra, Ford, Clemens, Jeter and Alex Rodriguez. Outfield walls, signage, Yankees carpeting, even the historic organ used from 1967 to 2003 will be sold.

The bulk of the 1,400-plus lot auction will cover the annals of baseball, but memorabilia from the other major sports and their heroes will be well represented.

Among the most coveted items in this sale will be the earliest known Mickey Mantle autographed game bat, one that Mantle ordered from the factory on April 17, 1951. Among other Mantle items will be a game-used, 1955 pinstripe jersey signed. The sale also features a game-used 1942 Joe DiMaggio pinstripe and a game-used Babe Ruth bat from the early 1920s; and Yankee team-signed balls from all eras.

Two paintings that have been exhibited in baseball’s Hall of Fame and at Mickey Mantle’s Restaurant in Manhattan are on the block. Both oil paintings are by sports artist Steve Sax. One of the paintings shows Babe Ruth’s fabled “Called Shot” from the 1932 World Series; the other depicts Lou Gehrig making his immortal farewell speech in 1939 at Yankee Stadium.

One item that’s certain to attract Japanese collectors is the bat that Sadaharu Oh used to hit his 790th career home run in 1978. The bat is signed and inscribed, with his milestone noted, in English and Japanese.

Other Yankees items

The auction offers a single-signed Gehrig ball; and a Ruth-signed and inscribed ball written to Bobby Heilman and dated “12/25/35” is among other single-signed Ruth items. Among other Ruth items are a Yankees pinstripe jersey worn in the early 1940s by Ruth at 20th Century Fox functions. A limited-edition of the famous Babe Ruth Farewell Game photo by Nat Fein also is available (No. 214 of 500, signed by Fein).

A couple of team-signed baseballs, both very uncommon to the marketplace, are in the sale. A “Babe Ruth Home Run Special” ball from 1931 is signed by 21 members of the Yankees from that year, including Ruth on the sweet spot, Lou Gehrig, Tony Lazzeri, Earl Combs, Red Ruffing and Bill Dickey. The other ball is a team-signed ball from the 1928 World Champion Yankees, with Ruth on the sweet spot, Lou Gehrig, Tony Lazzeri, Earle Combs, Leo Durocher, Waite Hoyt, Herb Pennock, a total of 20 signatures all told. Another item is a framed display showing a program, ticket and signed photo of Roger Maris from the date, in which Maris slugged his then-record 61st home run of the season.

Meanwhile, the home jersey Jim Leyritz wore when hitting his game-winning home run in Game 4 against the Braves in 1999. It would also be the last major league home run hit during the 20th century. What’s more, the actual home run ball completes the memorabilia trifecta.

On top of that, a 1942 Joe DiMaggio game-used home flannel jersey will be on the block. The jersey features a blue “Health” patch on the left sleeve, which dates the jersey specifically to the 1942 season.

Among other Yankees items are:

• A 1900s New York Yankees (Highlanders) framed stock certificate with a photo of Hilltop Park • Yankee Stadium Opening Day program (unscored) from April 18, 1923 • A game-used Ruth bat dated to 1922 to 1924 • A 1926 Ruth single-signed baseball • A Gehrig single-signed baseball in brown fountain pen on the sweet spot • A twice-signed Ruth check from Oct. 5, 1945 • Mantle game-used bat from 1961-63, from former player Robert Cerv • Framed Ruth photo supporting the World War II troops, signed • A game-used Alex Rodriguez road jersey from 2004 • A 1999 game-used World Series road Bernie Williams jersey; • A 1999 game-used Roger Clemens road jersey • A framed 2001 World Series game-used base signed by Randy Johnson and Curt Schilling and seven Yankees, Luis Sojo, Paul O’Neill, Mariano Rivera, Jorge Posada, Roger Clemens, Derek Jeter and Tino Martinez • A game-used and autographed Whitey Ford bat from 1961-67 • Late 1970s game-used Thurman Munson Yankees cap, signed on the bill