"We're still 29-9," Boston coach Doc Rivers said after Friday's 98-83 loss at Cleveland. "This is a tough stretch. I don't like it. But we're going to right the ship. When? I don't know."

If recent history holds true, that could come at the start of a home-and-home series against the Raptors (16-21). The Atlantic Division-leading Celtics have won six of the past seven games with the Raptors, three straight in Toronto and both meetings this season.

However, when the teams met twice in November, Boston was headed toward a league-record 27-2 start. The Celtics' previous trip to the Air Canada Centre - a 118-103 victory on Nov. 23 came during a franchise-record, 19-game winning streak.

Toronto comes into Sunday's game on a season-best, three-game home win streak and a 4-1 in its last five overall despite starters Jose Calderon and Jermaine O'Neal missing time.

Calderon has missed four straight games due to a strained right hamstring, and a sore right knee has kept O'Neal out of the lineup since Dec. 29. Their status is unknown for Sunday's contest.

"We won the games we felt we were supposed to win," the Raptors' Chris Bosh said after Friday's 103-82 thumping of struggling Memphis. "We're just trying to keep everything moving. We know the schedule is going to get a little bit more challenging from here on out."

Since replacing O'Neal in the starting lineup, former top overall pick Andrea Bargnani has averaged 21.7 points and shot 63.3 percent from 3-point range (19-for-30). Will Solomon, back in the NBA after a six-year absence and Calderon's replacement at point guard, has reached double figures in consecutive games.

Bosh has also averaged 26.0 points and 10.0 rebounds over the past four games.

After averaging 102.3 points during its first 29 games, Boston has scored 92.9 during a 2-7 stretch and 90.5 during the four-game skid.

The Celtics topped 90 points in 24 of their first 29 games, but have failed to reach that mark in six of their last nine. Boston has also shot 45.5 percent from the floor in those nine games and 42.1 percent during its slide.

One player who's been remained steady despite Boston's poor play of late has been Kevin Garnett.

He shot 52.5 percent and averaged 16.2 points while playing 28 of the Celtics' first 29 games. His numbers are nearly identical despite Boston's recent woes, as he's averaging 15.6 points on 52.1 percent shooting.

Another who's played even better is Paul Pierce. He averaged 18.2 points on 41.1 percent shooting during Boston 27-2 start, but is averaging 22.7 points on 51.6 percent shooting over the last nine.

Pierce, who averages a team-leading 19.2 points per game, scored a season-high 36 against the Raptors in a 94-87 win on Nov. 10 at home.

The Celtics and Raptors will meet again on Monday in Boston.