SYRACUSE, N.Y. — Gritty Syracuse is atop the national rankings after playing second fiddle to Arizona for two months, and the Orange’s perfect season is intact after another single-digit victory.

Syracuse (22-0, 9-0 Atlantic Coast Conference) beat Notre Dame 61-55 on Monday night, its fourth win by six points or fewer, to remain one of two unbeatens along with No. 4 Wichita State. Off to the best start in school history, the Orange are on top of the poll for the first time since a six-week run in 2011-12, and it’s the 15th week all-time Syracuse has been No. 1.

“None of us talked about it,” said Trevor Cooney, who rescued Syracuse against the Irish with a career-high 33 points. “It’s just a number right now. We want that number at the end of the season.”

Combined with No. 1 Arizona’s first loss of the season last weekend, the Orange’s 91-89 overtime win over Duke on Saturday moved them up one spot to the top.

Syracuse (21-0) received all 65 first-place votes from the national media panel Monday, making the Orange the first unanimous No. 1 since Duke was for six weeks in 2010-11.

“We’re happy to be No. 1,” coach Jim Boeheim said. “Obviously, it’s taken a lot of hard work. It’s an honor. We’ll try to keep playing well.”

Syracuse is the fourth team to hold the No. 1 ranking this season. Kentucky was on top for the preseason poll and one in the regular season while Michigan State was No. 1 for three weeks and Arizona, which lost to California hours after Syracuse beat Duke, for the last eight.

Arizona (21-1) and Syracuse, which were 1-2 for the last eight weeks, switched spots this week.

Florida, Wichita State, the only other unbeaten in Division I, and San Diego State remained third through fifth and were followed by Villanova, Cincinnati, Kansas, Michigan State and Michigan.

Duke, which also won at Pittsburgh last week, was 11th, a jump of six spots from last week’s poll.

No. 20 Virginia, No. 22 Connecticut and No. 23 Gonzaga returned to the rankings. They replaced Ohio State and Wisconsin, which both reached as high as No. 3 this season, and Massachusetts.