Doc Rivers couldn’t help but quip. Asked Sunday about the Knicks’ lack of bench production, the Milwaukee Bucks’ head coach interjected with a line about Tom Thibodeau’s reputation for relying heavily on his starters. “Has Thibs ever played the bench?” Rivers said with a laugh before his Bucks’ faced Thibodeau’s Knicks at Madison Square Garden. “I’m joking, I’m joking!” But Rivers’ comment, while made in jest, came during a season in which the Knicks began Sunday ranked dead last among NBA teams in bench scoring (19.9 points per game) and rebounding (9.8 per game) while getting the fewest minutes out of their reserves. The Knicks entered Sunday’s matinee with a 25-14 record — good for third in the Eastern Conference — thanks largely to an excellent, and healthy, starting five. But the Knicks had lost four of five games, including Friday’s 25-point blowout by the Oklahoma City Thunder at the Garden, highlighting their depth issues. It’s a situation Rivers can relate to. He recalled coaching the Los Angeles Clippers a few years ago at the Garden and having to lean on Lou Williams, who had gone out in the city the night before. “He wanted to come out,” Rivers said. “He said, ‘Coach, I’m not drunk, but I’m hungover.'” Williams recently told his version of the story, saying on “The Underground Show” that he was still drunk at game time. Rivers, he said, told him he needed to sweat out the alcohol in time for the fourth quarter. Rivers said Sunday, “The truth is I look down [the bench] and I’m thinking, ‘Lou’s our best option.’ That happens at times. It’s tough, but you’ve got to [have] trust, and then we find out a lot of times you just can’t. When that happens, it does limit you. It limits your choices. You have to play guys bigger minutes.” “If that’s what [the Knicks] are doing, they’re doing it for a reason,” Rivers said. “One thing we know as coaches: We see everybody every day in practice. We know exactly how guys are playing and who you can trust for the most part.” The Knicks traded two key players — forward Julius Randle and guard Donte DiVincenzo — less than a month before the season to acquire star center Karl-Anthony Towns from the Minnesota Timberwolves. Mitchell Robinson continues to rehab from May’s ankle surgery, while Landry Shamet, Precious Achiuwa and Miles “Deuce” McBride have all missed time with injuries for different stretches this season. Last season, the Knicks ranked 27th in bench scoring (28.4 points per game) and 24th in rebounding (13.9). The Knicks beat the Bucks, 116-94, at MSG in November in the teams’ first meeting of the season. Rivers said he had not noticed the Knicks doing anything differently during their recent skid. “The ball’s not going in,” Rivers said. “They also have played some pretty good teams. They played Oklahoma [City] twice. That’s probably not healthy for anybody.” BIG KAT In that November win against the Bucks, Towns erupted for 32 points, 11 rebounds and five assists in 32 minutes. He shot 12-of-20 from the field, including 4-of-8 from 3-point range, and repeatedly blew past the more stationary Brook Lopez — a defensive matchup Rivers described Sunday as a “stupid” one to have assigned. Towns, 29, entered Sunday averaging 25.2 points per game on 55.2% shooting and a career-high 13.9 rebounds per game. Asked what Towns is doing differently compared to his nine seasons with Minnesota, Rivers cited multiple areas of improvement. “He’s always rebounded, but it just seems like his rebounding has been spectacular,” Rivers said. “I don’t think he settles as much here. Before [Anthony Edwards], he basically could take every shot and do whatever he wanted, and now I think he feels a responsibility [to] his teammates now.” “He has really good teammates,” the coach continued. “He has a team that is serious about going deep, and I think he feels that responsibility, so his shot selection is drastically improved and better. And then the last thing, I think he’s taking the ball off the dribble way more than he ever has.”