Rajon Rondo, Kevin Garnett, Kendrick Perkins, Paul Pierce, Ray Allen and Leon Powe watch the final seconds of Thursday’s loss at Washington click away.

AP / Pablo Martinez Monsivais

BOSTON — Boston coach Doc Rivers saw this coming.

He just didn’t know how far the Celtics would fall.

“I kept saying, ‘We’re not playing well.’ Now you guys believe me,” Rivers said, talking about how the Celtics were winning a lot of games that they did not deserve to win during their 19-game winning streak. “You could see where the team was headed. And we’re in it right now.”

Boston has lost seven of its last nine games entering today’s clash with the Toronto Raptors, including four straight.

“I’m a little surprised,” Boston point guard Rajon Rondo said of Boston’s slide. “We need to figure it out — quickly. I’m sure we will. We’ll stick together. This is a tough time for us right now, but we just have to handle the adversity. I’m sure we are going to bounce back from it.”

The banged-up Celtics hope to get back on track against a Toronto team that is 8-9 at home and is near the bottom of the Atlantic Division with a 16-21 record.

“We’re in a slump right now, so we have to find a way to get out of it,” Rondo said.

The Celtics are expecting the Raptors, who have won four of their last five games, to be at their best.

“We are getting every team’s best shot,” Rondo said. “The guys are playing extremely well against us every time we play one particular team. We have to come out every night, and it starts with defense. We have to talk more, communicate better and get it done on the offensive end as well.”

Rondo said that you can throw the records of their opponents out of the window because every team that plays the Celtics treats the game as if it were Game Seven of the NBA Finals because every team wants to beat the defending world champions.

The Celtics have lost to three teams with a record below .500 during this stretch. They lost to a Portland team that played without its leading scorer in All-Star Brandon Roy, and to the Houston Rockets, at home, who were without All-Star Tracy McGrady and starting forward Shane Battier.

“We just need to get down and dirty,” Rondo said. “Fight for the loose balls and win the hustle plays. I think we’ve been getting beat in the hustle areas. Not in the whole game, but in key possessions teams are out-hustling us. We’re not coming up with the stops and the big plays.”

Even with the recent struggles, Boston is still in first place in the Atlantic Division.

“We put money in the bank with the 19-game winning streak and we are making a withdrawal that we don’t want to have to make right now, but we are,” Rivers said after Boston lost to Cleveland on Friday night.

“At the end of the day, we are 29-9, which is not all bad except for the stretch that we are on right now, so we just have to get it right. We are going to right the ship. When? I don’t know, but the last two games — I’ve seen better stuff.”

Fatigue and injuries could be part of the reason for Boston’s struggles.

Kevin Garnett has “soreness all over his body,” Rivers said, and Rondo had to have his left shoulder wrapped during the morning shoot-around before playing Cleveland on Friday.

Kendrick Perkins is playing through shoulder pain as well, and Tony Allen has missed the last three games with an injured right ankle, so the All-Star break can’t come soon enough.

“Everything we are going through right now is tough times, but it can only make you stronger,” Rondo said. “What doesn’t kill you makes you stronger, and we’ll find a way.”

Toronto is coming off an impressive 21-point victory over Memphis on Friday night. All-Star forward Chris Bosh scored 32 points and pulled down 10 rebounds in that game. Center Andrea Bargnani added 21 points. The Raptors knocked down 55.6 percent of their shots.

roblee@projo.com