The game was not as close as the score indicates. The Cavs led by as many as 25 points and were ahead by 22 when the fourth quarter began. The Raptors didn't really cut into the lead until garbage time.
Cleveland has now beaten Toronto three consecutive times in the playoffs dating to last season's Eastern Conference finals. And all five of the Cavs' wins over the Raptors in the postseason have come by double digits.
The average margin of victory in the last series was 15.5 points.
"I don't think about the past or the future," said James, who added 10 rebounds and four assists. "I worry about the present. That's all my whole mindset is how we can get this win today, Game 1, how can we get this win? How can we play? What can I do to help our team be successful?
"That's how I'm able to stay fresh because I don't think about the past and the future is a mystery. Gotta live in the present."
James also tied Kobe Bryant for second place in league history by scoring at least 30 points in a playoff game for the 88th time.
Irving added 10 assists for Cleveland after posting just 12 assists through the entire first round. Tristan Thompson contributed 11 points and 14 rebounds, and Kevin Love finished with 18 points and nine rebounds.
The Cavs have opened the 2017 playoffs with five consecutive wins. Monday's game was their first since a first-round sweep of Indiana ended April 23.
The Raptors were led by 20 points from Kyle Lowry and 19 from DeMar DeRozan, who averaged 29.7 points against the Cavs during the regular season. P.J. Tucker had 13 points and 11 rebounds, and Serge Ibaka added 15 points for Toronto, which is now 1-12 in franchise history in Game 1 of any playoff series.
"It seems the same," said Lowry, who recorded 11 assists. "They get big spurts, and we fight back. We have to find ways to eliminate the spurts.
"We know that they are going to be a high-flying team that likes to get up and down. But we have to find a way to not let them get going and get the crowd involved."
Cleveland scored 12 more points on 3s than the Raptors (14 3-pointers to 10) and seven more from the foul line.
The Cavs led 30-18 after one quarter, punctuated by a nifty alley-oop off the glass from Irving to James for a dunk early in the quarter, and a nasty dunk by Iman Shumpert (five points) over Ibaka late in the quarter.
"They were off for a week and they were fresh, but it wasn't like we had just finished playing," Toronto coach Dwane Casey said. "We had a couple days of rest, but we have to switch gears from the Milwaukee series to this series. I thought they were the quicker team tonight and we have to match that."
The Cavs are now 16-1 at home in the Eastern Conference playoffs dating to 2015 and 29-4 overall.
Also like last year, Dahntay Jones mixed it up with Raptors players late in the game and owes the league some money as a result. Jones, who signed on the final day of the regular season, was whistled for two technicals on the same play with 18.7 seconds left in the fourth quarter. It will cost him $6,000 in fines.
Last year, Jones was suspended for a game for punching Bismack Biyombo in the groin. Then and now, James offered to pay the fine.
"I actually told him ... first of all, I said I was going to pay the fine before I even knew what it was," James said. "It didn't matter. And I told him tonight, I said, 'Listen Dahntay, now enough is enough. Stop getting kicked out against Toronto all the time. I'm gonna stop paying your damn fines.'
"But yeah, he don't have to worry about it. He's good."
NOTES: The Raptors' last win in the first game of a playoff series was May 6, 2001, at Philadelphia in an Eastern Conference semifinal. They've lost their last 10 openers. ... Raptors coach Dwane Casey would not say 90 minutes before game time whether he was starting Jonas Valanciunas or Norman Powell. Valanciunas, a 7-footer and usual starter, got the nod and finished with six points and six rebounds. Casey used Powell in a small starting lineup for Games 4-6 against the Milwaukee Bucks in the first round and the Raptors won all three games. ... Cavs coach Tyronn Lue left G Iman Shumpert in his nine-man rotation ahead of Richard Jefferson, and the result was a posterizing dunk by Shumpert over Raptors F Serge Ibaka late in the first quarter. ... Paul Pierce, who played his last NBA game on Sunday with the Los Angeles Clippers, led the last Eastern Conference team to beat LeBron James in the playoffs. The Boston Celtics bounced the Cavs from the East semifinals in 2010.