Darien took the spot after the Hill Academy, located in Ontario Canada lost on Sunday.
The Darien squad is now 8-0 and boasts the nation's longest winning streak, which now stands at 40 games, Inside Lacrosse.
Brunswick School in Greenwich and New Canaan also made the rankings, coming in at No. 12 and No. 19, respectively.
Click here to view the complete rankings.
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