PHOENIX (AP) — The start of conference season usually means plenty of match-ups between AP Top 25 teams.

This week is overloaded with ranked-on-ranked games with nine.

It starts Tuesday night when newly top-ranked Baylor plays at No. 10 West Virginia.

The Bears have gone from afterthought early in the season — no votes in the first two AP polls — to their first No. 1 ranking this week.

Baylor (12-0) and No. 5 Gonzaga (15-0) are the only undefeated teams left in the poll, but the Bears' reign at the top will get tested right away with a game against the tough-to-play Mountaineers. West Virginia dropped three spots in this week's poll after losing to Texas Tech last Tuesday.

"It's great to be No. 1, but it's kind of hard to really appreciate knowing we have to go to West Virginia," Baylor junior forward Terry Maston said.

It doesn't get any easier for Baylor if it gets past West Virginia. On Saturday, the Bears head to the Little Apple to face No. 25 Kansas State, which entered the poll this week after beating Oklahoma and playing rival Kansas close in Lawrence.

Also Tuesday, No. 3 Villanova get a stiff test in its first game since being knocked from No. 1, facing No. 15 Xavier, and No. 7 Duke plays at No. 9 Florida State.

Wednesday has No. 8 Creighton playing at No. 12 Butler.

Saturday has four other games involving two ranked games beside Baylor-Kansas State: No. 5 Gonzaga at No. 21 Saint Mary's, No. 7 Duke at No. 14 Louisville, No. 9 Florida State at No. 11 North Carolina and No. 12 Butler at No. 15 Xavier.

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VILLANOVA'S FALL

Villanova had an impressive run to start the season in defense of its national championship, sitting atop the poll for five weeks while stretching its winning streak to 20 combined games.

The Wildcats suffered their first setback on Wednesday, when Butler bogged the game down and beat them 66-58 .

"It stings right now," Villanova preseason All-America Josh Hart said. "But we're not going to be discouraged by it."

Villanova bounced back (15-1, 3-1 Big East) nicely on Saturday, rolling over Marquette 93-81 . The Wildcats will face St. John's at Madison Square Garden Saturday after Tuesday's game against Xavier.

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ZAGS' TEST

Gonzaga may have coach Mark Few's best team of his 17 seasons in Spokane and have played like it, beating No. 15 Arizona, No. 23 Florida and blowing out most everyone else.

The Zags get a big test on Saturday when they play their main rival in the West Coast Conference, No. 21 Saint Mary's .

The Gaels (14-1, 4-0 WCC) suffered a surprising loss to Texas-Arlington on Dec. 8, but have since reeled off eight straight wins.

These games are always entertaining so be sure to tune in.

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WATCH LIST

Seton Hall (12-3, 2-1 Big East) was the top team receiving votes in this week's poll and could move into the top 25 next week with a couple of wins. The Pirates play at Marquette on Wednesday, then at Providence on Saturday.

Indiana (11-5, 1-2 Big Ten) has been a hard time to figure out, going from as high as No. 3 in the AP Top 25 to out of the poll this week. The Hoosiers have wins over Kansas and North Carolina, but lost to Fort Wayne and had a three-game losing streak before beating Illinois on Sunday.

South Carolina (12-3, 2-0 SEC) could be on the verge of being ranked again. The Gamecocks were No. 22 three weeks ago and won both of their games last week, beating Georgia and Texas A&M.

South Carolina faces Tennessee and Ole Miss this week.

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