After a weak start this year, the American Athletic Conference is beginning to flex its muscles in men’s basketball. Lately, that strength has been too much for Tulane to handle.

The Green Wave, picked last by the coaches before its first season in the AAC, has lost five of seven since winning at East Carolina and Memphis in its opening two games. The defeats have left Tulane (13-8, 4-5) under .500 in the league standings for the first time in the midst of a slew of games against the league’s upper division.

“We’ve had really good opponents that have tested us,” coach Ed Conroy said. “Every night in this conference is really a battle.”

Clearly, the AAC has recovered from a horrendous November and early December that made its supposed basketball prowess look as shaky as its football shortcomings.

Defending NCAA champion Connecticut, ranked 17th in the preseason despite losing four starters, lost consecutive games to West Virginia, Texas and Yale. That’s right, Yale, which beat the Huskies 45-44 in Storrs, Connecticut.

Memphis, coming off four consecutive NCAA tournament appearances, lost by 15 to Wichita State, by 24 to Baylor, by 18 to Oklahoma State and by 12 to Stephen F. Austin. That’s right, Stephen F. Austin, which handled the Tigers 64-52 in Memphis.

SMU, ranked 22nd in the preseason under Hall of Fame coach Larry Brown, lost the first three games it played against teams with a pulse — Gonzaga, Indiana and Arkansas.

A couple of schools that made splashy coaching hires drowned in bad results, too.

Tulsa, the Conference USA tournament winner a year ago, convinced Missouri’s Frank Haith to leave the SEC for the AAC to replace departing coach Danny Manning. The Golden Hurricane then lost its opener at Oral Roberts, 77-68, and followed with an even more embarrassing home defeat to Division II Southeast Oklahoma State.

Houston hired former Oklahoma and Indiana coach Kelvin Sampson after he emerged from NCAA purgatory, then dropped back-to-back home games against Arkansas-Pine Bluff and South Carolina State.

By week five, no AAC team received a single vote in the AP poll, which had 44 teams with at least one.

The turnaround started two weeks later, when SMU won comfortably at Michigan and Temple clobbered 10th-ranked Kansas 77-52. Cincinnati followed with a 16-point victory at North Carolina State.

Flash forward to the midpoint of the conference season, and everything has changed. The AAC, which looked like it might be a one-bid league entering January, has three teams in the top 41 of ESPN’s RPI calculations — No. 23 SMU, No. 30 Cincinnati and No. 41 Tulsa. Temple is not far behind at No. 51, so the league is within range of the four NCAA tournament bids it received a year ago, when Louisville was a member.

SMU (17-4, 8-1), which has won 15 of its last 16, likely will return to the AP top 25 if it beats UCF at home on Saturday. The Mustangs cracked the top 30 this week.

Tulsa (15-5, 8-0), the surprise of the league, has won 19 consecutive conference games dating back to last year in Conference USA.

“We’re getting production out of our bench, we’re playing great team defense and our guys are getting better,” Haith said after Tulsa’s 63-55 victory over Tulane on Tuesday. “We’ve been growing as a team, and we’re doing it in a great league.”

With the AAC beginning to live up to its preseason hype, the Wave’s task to stay afloat has become much tougher.

“Every game in the American Conference is hard-fought,” Conroy said. “We’ve proven that we can compete with these teams. We’ve just got to get over the hump.”