Last Friday, they gave up 73 points to Cleveland – in the first half.

The next night, they gave up 70 points to Orlando – in the first half.

But there they were on Monday, bodying up, covering for one another, contesting shots and generally playing in a frenzy while holding Charlotte to 18 points in the fourth quarter in a 105-96 victory.

Dr. Jekyl, meet Mr. Hyde. And tell him to D up, will you?

The Pacers have tended to go to extremes on defense this season, taking quarters and halves off now and then but getting down to business when a crisis strikes. And they have become familiar with crisis, coming back to win games from deficits of 19 points or more five times. It takes great defense to make that kind of surge. But then it takes poor defense to make such a surge necessary.

“I don’t know what it is,” Lance Stephenson said following Tuesday’s practice at St. Vincent Center. “We’ve had a lot of games in the first half where teams score 65 or 70 points. I feel if we stay close in the clutch part of the games we play very good defense. I don’t know what it is … as long as we’re winning.”

Winning makes a lot of flaws more palatable, and the Pacers’ 28-23 record heading into Wednesday’s game against Memphis at Bankers Life Fieldhouse is far superior to the general preseason expectations. Still, Pacers coach Nate McMillan and defensive coordinator Dan Burke would prefer more consistency and less drama.

That begins on the defensive end, where the Pacers tend to establish an energy level that influences their offense. When they are getting steals and stops, the tempo increases and the offense comes much more quickly and easily than when they are taking the ball out of the net after a made field goal and jogging upcourt. Getting to that point has been a challenge for Burke, but he sees improvement.

The Pacers rank 18th in defensive efficiency, which measures the average points they allow per possession over 100 possessions. They rank 12th in points allowed, and 21st in defensive field goal percentage. In other words, they have been decidedly mediocre over the course of the season. On average, they score just one more point than they allow, so they are living on the edge.

Their ability to lock down at the most crucial moments offers hope, however, as does the performance of certain individuals. Victor Oladipo leads the NBA in contesting 3-point shots (five per game), while Thad Young ranks second. Young is tied for third in deflections (3.7) – former Pacer Paul George is first – while Oladipo is tied for ninth.

Backup guard Cory Joseph, who often finishes games in place of starting point guard Darren Collison, is a physical defender who often takes on the biggest challenge successfully.

“He does a good job of disrupting with his pressure,” McMillan said. “Most of the time he’s in the right position. He stays in front of the ball. We’re playing him on ones, twos and threes. He’s been the one defender from our guard position who’s been consistent.”

Stephenson, meanwhile, seeks that level of consistency. He’s often lacked focus in the routine moments of games, but becomes a Doberman in the fourth quarter of close games. He was outstanding, for example, on Monday. Hornets guard Nicolas Batum had scored 20 points through the first three quarters, but in the fourth managed just two points on 1-of-3 shooting in 7 ½ minutes against Stephenson - and that one made field goal was a well-defended 20-footer.

Stephenson had asked to switch on to Batum to take the burden off Oladipo, who then was able to save more energy for offense while taking on the lesser challenges of Jeremy Lamb or Michael Carter-Williams. That’s something Joseph has done on occasion this season, but is a relatively new gesture from Stephenson.

“Typically, Lance isn’t out there with the defensive group when we need stops, but he’s earning our trust more and more,” Burke said. “The job he did on Batum was tremendous. He was into him early, being physical.

“When he’s focused, he’s got great length, great strength, guys don’t like the way he guards them. (He needs to) trim down some of the antics that get him more notoriety for the wrong reasons. But he’s helping us win. Lock in every play, do what your teammates need you to do, he’s going to keep earning that trust.”

Burke doesn’t mind Stephenson’s occasional lapses into showmanship, or away from the game plan, in moderation, as long as he’s bringing energy and playmaking.

“If you have a classroom of just A students, it’s probably going to be boring,” Burke said. “Guys like him, it makes it a little more fun. It’s a challenge. Love his passion for the game. He’s one of those guys you can be so angry at, but you have to hide your face because you’re laughing at something he said back to you.”

The Pacers also have a bona-fide shot-blocker in Myles Turner – the best in the NBA, in fact, when he’s played enough games to qualify for the league rankings. Turner will be back in the starting lineup on Wednesday, bringing the length and timing that backup center Domantas Sabonis lacks. Sabonis, however, brings a physicality that Turner lacks. Between the two of them, they can deal adequately with opposing centers.

The Pacers’ greatest flaw on defense can’t be coached: length. They match up well with the conference finalists of 2013 and ’14 in energy and cohesion, but don’t have a 7-foot-2 center such as Roy Hibbert, a long-armed 6-3 point guard like George Hill or a 6-9, first-team all-defense member such as George. Or, a natural leader such as David West, who played like a linebacker calling out signals.

“We don’t have the versatility we had with that group,” Burke said. “We don’t have that stalwart behind us like David West. It took just one bark and they were like, ‘We’re in, we’re in.’ We’re small, but we’re fast and feisty. We have to keep building on that.”

The Pacers’ defense is no different than their offense or leadership. It has to be a collective effort to be successful, a by-committee approach that relies on balance rather than individual stardom. Burke tries to get that across in his film sessions – the ones Stephenson smilingly professes to hate. They are generally 10 or 15 minutes long, and include about 20 clips from the previous game.

Burke tends to point out possessions in which four defenders do their job, but one makes a mistake that allows a basket or causes a foul.

“This is why we need five guys,” Burke tells them. “This is why you can’t take a play off.”

The Pacers have taken plenty of defensive plays off this season. Reducing those occurrences will go a long way toward extending their season.

Have a question for Mark? Want it to be on Pacers.com? Email him at askmontieth@gmail.com and you could be featured in his next mailbag.

Mark Montieth's book, "Reborn: The Pacers and the Return of Pro Basketball to Indianapolis," covers the formation and early seasons of the franchise. It is available at retail outlets throughout Indiana and online at sources such as Amazon and Barnes & Noble.

Note: The contents of this page have not been reviewed or endorsed by the Indiana Pacers. All opinions expressed by Mark Montieth are solely his own and do not reflect the opinions of the Indiana Pacers, their partners, or sponsors.