Another new "substantial" Takkle investor is the New York City Investment Fund, which was created by Henry R. Kravis and Russell L. Carson. Birnbaum also reported new funding from Takkle's original investors: Wasserman Media Group LLC's WMG Investments, Greycroft Partners, LLC (founded by Alan Patricof), IJ Smith Enterprises LLC, and Jack Schneider, managing director at Allen & Company.

Birnbaum said he couldn't reveal the amount of the new funding round, or the number of current Takkle members. He did, however, say that users in the "four digits" (between 1,000 and 9,999) were coming on board every day.

Under the ongoing content-sharing partnership with Sports Illustrated, Takkle carries articles and other editorial content from SI.com, and SI.com can feature video clips from Takkle members. Takkle also serves as the exclusive high school nomination platform for Sports Illustrated's "Faces in the Crowd" feature. In addition, Takkle features a weekly Video Face in the Crowd in both the magazine and on SI.com, with the athlete's video highlights and profile available exclusively on Takkle.

Recently, Takkle launched a photo contest, with ten first-prize winners featured in an online gallery at Takkle, and the winning photo also running in Sports Illustrated's print edition.

Through its partnership with SI, Takkle said it has created sponsorship programs for leading brands such as Gatorade and Finish Line.

Separately, on Friday, Takkle said it had signed basketball equipment supplier Spalding, a division of Russell Corp., as sponsor of a new 3-Point Battle competition. High school basketball players will submit videos of themselves hitting the most consecutive 3-point basketball shots. Live events will also take place in seven cities.

Birnbaum said that one of the results of the new funding will be many more such combinations of online activities with offline, in-person events, with soccer and lacrosse versions of its Battles on tap, among others.

Other Takkle sponsors since launch have included Procter & Gamble and Met-RX. The site has also secured partnerships with Five Star Basketball, Baseball Factory, MSL Sports, Offense-Defense Football Camps, Womenslacrosse.com, and Brine.

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