"This game's a mystery to me," Lakers coach Phil Jackson said after the Lakers humiliated the Suns 87-65 Tuesday night to win the best-of-7 Western Conference semifinals in five games.

"How's that for killer instinct?" wondered Kobe Bryant, the game's high scorer with 17 points.

Phoenix held a 71-48 halftime lead en route to a 117-98 victory on Sunday to force a fifth game. The 117 points were the most scored by a Lakers' opponent this season.

In Game 5, the Suns equaled a playoff record for futility in the first half, scoring only 23 points. And their final total of 65 fell six points short of their first-half output two days earlier.

"We just couldn't make shots," Suns coach Scott Skiles said. "We had a bunch of open looks, we just didn't make them."

Shaquille O'Neal had 15 points, 21 rebounds and three blocked shots despite sitting out the fourth quarter for the Lakers, who face Portland in the best-of-7 conference finals, starting Saturday at Staples Center.

The Trail Blazers eliminated the Utah Jazz on Tuesday night, also in five games.

"Team-wise, we played an inspiring game," O'Neal said. "Personally, I didn't play that well, but my teammates stepped up for me. We played great defense and were real active with our hands. We came out and took it to them. We got a lead and never lost our focus."

Jackson didn't agree with O'Neal's assessment of his play.

"I thought he was real dominant in the game," Jackson said. "I thought he changed shots, controlled the boards. He played with a little bit of a banged up knee, banged up shin."

O'Neal was injured Sunday and wore a sleeve on his lower right leg.

The Suns were a beaten team by late in the second quarter, and it showed in their body language after they continued to miss shot after shot, many unopposed.

The Lakers had two 10-0 runs in the period on their way to a 49-23 halftime lead.

"I think the reason we were so frustrated was because of all the trash-talking they did before the game," said Penny Hardaway, who was held to eight points after averaging 24.8 in the first four games. "I think that had everybody's adrenaline going, and then not to be able to knock down those shots kind of demoralized us."

The Suns' 23 first-half points tied the playoff record in a half set by Utah in the second half of a 96-54 loss to Chicago Bulls on June 7, 1998 in the NBA Finals. The 54 points are the playoff record low for a game.

The Suns also tied the playoff record for futility in a second quarter, when they scored nine to the Lakers' 28.

Phoenix shot 2-of-17 in the second quarter (11.8 percent), and 8-of-37 in the half (21.6 percent).

"We wanted to be more aggressive defensively, run the fast break and get them in foul trouble," said Glen Rice, who had 14 points for the Lakers.

That's exactly what happened.

Cliff Robinson, who averaged 24.5 points previously in the series, picked up his third foul three minutes into the second quarter, and sat out the remainder of the half. He finished with eight points.

Penny Hardaway goes up for a basket as Shaquille O'Neal defends.(AP)

Center Luc Longley also picked up his third foul in the second quarter.

Todd Day led the Suns with 10 points, all but two in the fourth quarter. Jason Kidd, who had 22 points, 10 rebounds and 16 assists for his first playoff triple-double in Game 4, was held to eight points, seven rebounds and two assists.

The nature of the loss prompted veteran Los Angeles guard Ron Harper, a member of three championship teams with the Bulls, to say the Lakers played absolutely no defense in Game 4, and lacked a killer instinct.

The Lakers led 68-40 entering the fourth quarter, and reserves played much of the final period for both teams.

Bryant scored five straight points, and Rice followed with a 3-point shot to give the Lakers a 14-6 lead, and they were on top the rest of the way.

At one point early in the second quarter, in apparent frustration, Kidd threw up a jump shot several seconds after a foul had been called. Appropriately, he missed.

As the score mounted, the Suns committed several unforced turnovers.

Notes

• The NBA record for fewest points in a half in a regular season game is 19 by the Los Angeles Clippers against the Lakers last Dec. 14. The Lakers big three of O'Neal, Bryant and Rice scored their team's first 18 points. No other Laker scored until Harper made a layup with 50 seconds left in the first quarter.
• The Lakers finished the season with an 8-1 record against the Suns.
• The Lakers are 6-0 in playoff games at Staples Center, and have won 23 of 24 home games since a 95-91 loss to Portland on Jan. 22.
• The Suns' previous playoff low for a game was 70 points in a 15-points loss at San Antonio last month.
• The Lakers and Trail Blazers were 2-2 against each other this season, with each team going 1-1 on its home court.
• Robinson surpassed his playoff career high twice in this series with a 30-point effort in Game 2 and a 32-point performance in Game 4. He was never a factor in Game 5, shooting 3-of-11.