Poll these Georgetown basketball players on what they work on most in practice, and the answer, invariably, is defense. Senior center Omer Yurtseven said they’ll run through “every defensive drill you could think of.” The Hoyas have proven scorers on the roster, yes, from Yurtseven to point guard James Akinjo and the highflying Mac McClung. But on Coach Patrick Ewing’s team, defense matters most.

The only problem is that, three games into the season, Georgetown’s defense has yet to come to fruition.

Penn State handed the Hoyas their first loss, 81-66, as Georgetown was unable to overcome a start similar to the one it sleepwalked to in its first game of the season against Mount St. Mary’s. This time, when Georgetown’s defense arrived late and showed up disheveled and disorganized, Penn State made the Hoyas pay.

Ewing reeled off a litany of sins his team continues to commit in this year’s beefier nonconference slate. But lax defense from the beginning doomed the Hoyas above all else, leaving Ewing with much to address before Georgetown (2-1) heads to play Texas and either California or Duke in a tournament at Madison Square Garden next week.

“They beat us at everything,” Ewing said. “We turned the ball over 21 times, gave them 22 points off turnovers. They made their threes — 13 of 29 from three. . . . We also couldn’t make shots.”

Most of those varied woes stemmed from the Hoyas’ inability to get stops. Georgetown looked shellshocked early as the Nittany Lions (3-0) calmly sank five three-pointers on their way to an 18-point lead midway through the first half. After that, everything the Hoyas did in an effort to scrape their way back was haphazard, the rushed result of anxiety that was made most apparent in 13 first-half turnovers.

Georgetown never came within five points of the lead.

“I really can’t put my finger on it yet. Guys are in a slump, or we’re not sharing the ball. It’s a lot of different things. I don’t really have an answer for it yet,” Ewing said of the slow starts.

While Georgetown stumbled early, Penn State sophomore guard Myreon Jones feasted, scoring 14 of his career-high 21 points in the first 5:08. Lamar Stevens, Penn State’s leading scorer, had 14 points and nine rebounds.

Former first-team All-Met selection Myles Dread, a Gonzaga graduate, added 14 points.

Ewing, who did not permit players to speak to the media after the game, said he also can’t quite pinpoint why all of Georgetown’s defensive drilling in practice hasn’t yet translated in games.

“Well, sometimes I’m not seeing what I want to in practice, but it starts individually,” Ewing said. “You have to be able to stop your guy, at least make him work. And sometimes we’re not getting that done, or four guys may do it and one may not, or three may do it and two may not. So we have to do a much better job of, one, guarding our man, and then if we get beat, the help has to be there. Right now we’re not getting that done.”

The Nittany Lions shot 44.4 percent from the field and 44.8 percent from three-point range. Their 20 turnovers were nearly even with Georgetown’s 21, but they scored 22 points off giveaways while the Hoyas only managed 12.

Even when Georgetown flaunted the individual scoring prowess on its roster with mini bursts of momentum, such as when Yurtseven, Akinjo and junior Jamorko Pickett combined for a 9-0 run in the first half that looked like it was going to give the Hoyas some life, they never had control of the game. Penn State led from tip to tip.

“I thought our defense and our rebounding was timely,” Nittany Lions Coach Pat Chambers said. “They would go on a run, they would make a big shot, a big play, maybe steal the momentum just for a little bit, and then we were able to get a big shot or a big stop or a big rebound. I thought that was critical.”

Ewing said Georgetown, on the other end, “just did not handle the moment.”

“I don’t think it was anything they were doing defensively. We acted like we were a deer in lights,” Ewing said. “A couple times we turned them over, then we turned it right back over to give them the ball. They were switching, but that’s something we should be used to, other people switch against us.”

Without much on the defensive end, Georgetown was left to try to outshoot Penn State. Yurtseven led with 16 points and 10 rebounds for his third double-double in three games. Akinjo had 13 points. But after Penn State went up 18, the Hoyas never came closer than when a pair of free throws from Yurtseven brought the score to 42-32 early in the second half.

A three-pointer from Dread quickly stomped that momentum.