Late in the third quarter, Celtics rookie James Young hoisted a 3-pointer that missed everything: rim, backboard, net.

Christian Watford, however, was there to catch the basketball and jam it through the hoop.

It was that kind of night for the Maine Red Claws, who extended their perfect record to four games with a 120-102 victory over the previously-unbeaten Delaware 87ers in NBA Development League action Sunday evening.

A crowd of 1,811 at the Portland Expo saw the Red Claws get off to a slow start, falling behind by eight points in the first quarter before surging to a 10-point halftime lead that was never seriously threatened after intermission.

“We moved the ball well offensively,” said Red Claws Coach Scott Morrison, noting that two thirds of Maine’s field goals (28 of 42) came with an assist. “Defensively, we got back in transition and made them take tough shots. Even when they got to the rim, there was someone there to protect the hoop. I thought Ralph (Sampson III) and (Asauhn) Dixon-Tatum did a great job and made it difficult for them to get easy looks.”

Sampson finished with four blocks and Dixon-Tatum three. Young, on assignment from Boston, and Watford each scored 22 points. They also contributed eight and 13 rebounds, respectively.

Seven players contributed to Maine’s total of 18 three-point field goals, tying a team record set in a season-opening victory over Oklahoma City. The Red Claws achieved that mark on a Sherwood Brown trey with more than four minutes remaining and missed five more attempts at a record 19th. They finished 18 of 43 from long range for a 41.9 shooting percentage.

“If our defense is good and we shoot that well, we’ll probably win a lot of games,” Morrison said. “But it just doesn’t work that way. We’re not going to shoot 42 percent from three every night so we have to take better care of the ball.”

The Red Claws made 20 turnovers Sunday night to only nine for Delaware (2-1). Point guard Tim Frazier had three in the first quarter before settling into a better rhythm.

“You’ve got to go for the simple plays,” said Frazier, who had to leave the game for a stretch after an elbow to the nose drew blood. “Sometimes I go for the home run ball.”

Delaware cut the margin to five early in the third quarter before Maine went on a 39-14 run to reach triple digits and open the fourth with a 100-70 lead. Young, Watford, Omari Johnson (11 points) and Frazier (16 points, six assists) all hit from long range and the 7-foot Dixon-Tatum asserted himself in the paint, scoring all of his nine points in just over two minutes.

Young, who played only one year of college basketball at Kentucky before declaring for the NBA, said his directive from the Celtics coaching staff was to work on his defense. Morrison is happy to have the first-round draft pick’s offense as well.

“He’s behind some pretty good players in Boston so it’s nice for him to get some extended minutes to work on things both on offense and defense,” Morrison said. “For us, he brings a scoring threat that other teams have to focus on, and we can draw up plays where he’s both the first option to score but also kind of a decoy where he’ll drive into the paint and kick it out for open looks.”

Sunday marked Young’s second game with the Red Claws. He scored 21 points in last weekend’s 81-80 victory in Fort Wayne.

“I thought he also did a good job on the glass, got us some second chances and played pretty good on-the-ball defense,” Morrison said. “I hope he improves such that he gets into the rotation in Boston but obviously we’re happy any time they send him up to Maine.”