Javon Greene and Ian Boyd can smile and exhale after a tense win over U-Mass. (Jonathan Newton/The Washington Post)

It hasn’t been easy for the Atlantic 10 this season. Why should March be any different?

That was especially true Thursday afternoon for a George Mason team that is 12 years removed from the most glorious moment in school history, which took place in this building, back when it was known as Verizon Center. They weren’t going to the Final Four this time, but for now the quarterfinals of the conference tournament are just fine.

On Thursday, the Patriots couldn’t exhale until Luwane Pipkins, the Massachusetts guard who had already scored 31 points, was called for an offensive foul with 1.4 seconds left while trying to get in position for a potential game-tying three-pointer.

“With this league . . . every single game is a grind-it-out game,” George Mason Coach Dave Paulsen said after the 80-75 victory. “They are all going to come down to one or two possessions.”

Fitting, then, that the team’s next game will be Friday afternoon against fourth-seeded Saint Joseph’s, a team it has defeated twice this season — both on buzzer-beaters. The Patriots have won four games overall on their final offensive possession, including three straight games last month — all of those on baskets by sophomore Ian Boyd.

“We’re confident in close games,” said leading scorer Otis Livingston II, who recovered from a miserable six-point first half on 1-of-7 shooting to score 21, largely by getting inside and getting to the foul line, where he was 14 of 14. “Just about every single game is like this game. We’ve been through it before.”

Grind it out may best describe this season in the A-10. Nothing was easy — even for Rhode Island, which won the regular season title with a week to go, cut down the nets and then lost to Saint Joseph’s on senior night — by 30.

The league had its worst nonconference record since 2005. After 10 straight years in which it received at least three NCAA tournament bids, including a high of six bids four springs ago, only Rhode Island and St. Bonaventure figure to be in the 68-team bracket that will be unveiled Sunday.

The opening of Thursday’s afternoon doubleheader at Capital One Arena was evidence of how much the league is changing.

The opener matched VCU, the No. 8 seed, against Dayton, the No. 9 seed. This was the A-10 equivalent to Duke and North Carolina meeting in an 8-9 game in Brooklyn this week. VCU and Dayton are A-10 royalty. The Rams, who made a dramatic run to the Final Four in 2011 while still in the Colonial Athletic Association, have played in the last seven NCAA tournaments. Dayton has played in the last four, reaching the Elite Eight in 2014.

But the coaches who built those teams were nowhere in sight at high noon Thursday when the teams were introduced. Shaka Smart, who became a hero in Richmond after the 2011 run, was at the Big 12 tournament, trying to squeeze his Texas team into a bid come Sunday. Smart left for Austin three years ago. Will Wade succeeded him for two years before leaving for LSU last spring. And so it was Mike Rhoades, who was on Smart’s staff for the 2011 run, who whipped his coat off on the VCU bench even before the opening tip.

On Dayton’s bench, Anthony Grant (himself a former VCU coach) was in his first season as well, having replaced Archie Miller after he left last summer for Indiana.

Dayton was 24-8 a year ago, but Miller left behind a young, rebuilding team that only plays one senior. The Flyers entered Thursday’s game at 14-16, a record that doesn’t play especially well in hoops-mad Dayton. The Rams were 17-14 after going 26-9 last season under Wade. That hasn’t made life easy for Rhoades.

With 3:16 left, it looked as if life was going to get tougher for Rhoades. A second-round loss in the conference tournament and the likelihood of not even getting an NIT bid would have left the Rams faithful restless, even though Rhoades has probably coaxed as much as one could hope out of a team with eight new players.

Down 70-65, with the game and the season seemingly slipping away, Rhoades called a timeout. His message to his players was direct: “Get three stops, and we’ll win the game,” he said. “I promise.”

They got four. That led to a 10-0 burst that turned the game and allowed the Rams to escape with a 77-72 victory. Rhoades was able to breathe a sigh of relief, take a deep breath for about five minutes and start preparing to play Rhode Island on Friday afternoon.

That game will precede George Mason vs. Saint Joseph’s. The Patriots played Thursday in front of what would best be described as a small but enthusiastic crowd. It was a far cry from that remarkable Sunday afternoon in 2006 when Jim Larranaga’s Patriots stunned top-seeded Connecticut in overtime in front of a screaming, sellout crowd to earn a trip to the Final Four.

Nowadays, Paulsen is trying to make George Mason viable in the A-10, five seasons after the school decided to chase the TV money and leave the CAA. Paulsen took over three seasons ago and has steadily upgraded the team’s talent.

There are no seniors in the rotation, and all of his inside players are freshmen. Two of them, Greg Calixte and A.J. Wilson, combined Thursday for 12 of the team’s 20 offensive rebounds (to six for U-Mass.). They’ll be joined next season by 6-foot-7, 240-pound Virginia transfer Jarred Reuter. The Patriots should be one of the league’s favorites come November.

That’s then, though, and this is now. The league’s top teams this season were those with coaches who have had time to build their programs: Danny Hurley is in his sixth season at Rhode Island, Mark Schmidt his 11th at St. Bonaventure. The court at Davidson is named for Bob McKillop — in his 29th season — and Phil Martelli is in year 23 at Saint Joseph’s.

Among the four coaches in the building for Thursday’s afternoon session, including Matt McCall of U-Mass., only Paulsen wasn’t in his first season. All four were a little older by the end of the afternoon. It was a grind-it-out day in a grind-it-out league.

For more by John Feinstein, visit washingtonpost.com/feinstein.