The Heat’s winning record entering Monday’s game against the Suns gave coach Erik Spoelstra no comfort in the fact that his team’s defense has been subpar to begin the season.

In games against Boston, New York and Denver, the Heat allowed an average of 109 points per game. Last season, the Heat began the season allowing just 98.6 points in its first three games. Saturday night’s defensive effort in the paint was a particular point of concern. The Heat gave up 70 points inside to the Nuggets.

“We’re just doing things wrong, plain and simple,” said Chris Bosh, whose 40 points against Denver erased many of the Heat’s defensive errors. The Heat won the game 119-116.

“If we make mistakes we just have to listen to the criticism we give each other and know that it’s for the better of the team.”

Before Monday’s game, Spoelstra said there isn’t anything he can tell his players they don’t already know.

“Less conversation and just prove it,” Spoelstra said. “Just do it. We drill it, we work on it, we had a great training camp. … That’s what I’m looking for right now, action. We know how we want to play. We know what our identity is. We know playing like this isn’t going to get us anywhere.”

Hustle statistics told the story Saturday. In addition to the points in the paint, the Heat was outrebounded by the Nuggets 47-32 overall and 18-7 on the offensive glass.

“We’re at the point right now where we need one of our games defensively — where we’re capable, all five guys, of really impacting and making it tough on the other team regardless of the system they play,” Spoelstra said.

After Saturday’s game, the Heat’s defense was ranked last in the NBA in points per possession, a statistical measure Spoelstra emphasizes. The Heat allowed 1.022 points per possession in its first three games, according to SynergySportsTech, an advanced statistical database used by teams. What does that mean? It means the Heat has been below average in transition defense, terrible in overall half-court defense, lazy in defending jump shots and subpar in almost all defensive situations.

Consider this: Heat opponents were shooting 41.7 percent on jump shots before Monday, according to Synergy. Adjust the field-goal percentage statistic to account for the impact of three-point shooting (a measure known as effective field-goal percentage) and the Heat’s first three opponents shot 53 percent on jump shots.

“The first thing is owning it and knowing and we know,” LeBron James said. “We’ve won two of our three games, but it’s not the way we want to win. We make our mark defensively. We get stops, and that’s how we create our offense and it has been the other way around lately.”

Delving deeper into numbers reveals that the Heat’s helping defense was slow to react in the first three games. According to Synergy, the Heat’s first three opponents combined to attempt catch-and-shoot plays on 67 possessions. The majority of those possessions (50) were unguarded by the Heat. That means nearly 75 percent of the time, shooters were unguarded on catch-and-shoot plays. Not surprisingly, opponents shot 50 percent in those situations.

Granted, the Heat wasn’t very good at defending the catch-and-shoot last season either but, overall, the Heat’s defense was ranked fourth last season in points per possession (0.872).

Spoelstra and his players know it boils down to one thing, effort.

“We know we’re not going to win without it, but right now we can’t worry about that as much as everyone else is,” Dwyane Wade said. “We’ve got to come out every night and put a better effort forward and just feel ourselves get better defensively.”

Wade said three games is nothing to worry about, and the numbers would average out over the course of the season

Still, with a lack of size inside, Wade acknowledged that a more consistent effort defensively is needed.

“Obviously we’re not the biggest team in the league, so we’re giving up a lot when it comes to that,” Wade said. “I just think bottling up what we do in the last eight minutes of the game when we know it’s money time and just trying to bring that for as close as you can to the majority of the game.”