KEY POINTS:
On their biggest night of the season, the biggest Chief led the way to a rousing win at Jade Stadium.
The Chiefs got the victory they needed to stay in the semifinal hunt and No 8 Sione Lauaki was the catalyst.
His irresistable, thunderous charges, shrugging large men off like an outsize kid in a playground game, kept the Chiefs driving forward as they snapped the Crusaders' 26-game unbeaten home record.
And he capped a towering game with a deft kick ahead for wing Sitiveni Sivivatu to charge through, dive and score the try which sealed the win 7min from the end.
"We fought really hard for the 80min and I'm very proud of the guys," stand in captain and hooker Tom Willis said.
Lauaki continues to produce compelling arguments for an All Black recall. As for his kick for the decisive try "I was pretty surprised myself. I don't practice my kicking that much."
The Crusaders had the critical final say, Richie McCaw getting over the line on the hooter. It moved the defending champions to 42 points and guaranteed a home semifinal next week. Whether they finish first or second - and therefore get home hosting rights if they win their semi - depends on whether the Sharks beat the Stormers in Cape Town early tomorrow.
There were other Chiefs heroes. Stephen Donald maintained his outstanding season, and increased his lead as Super 14 top points scorer with six penalties and the late sideline conversion to ease the Chiefs clear.
Mils Muliaina outplayed his All Black fullback rival Leon MacDonald; the pack scrummaged forcefully, only coming under the cosh in the final quarter; Sivivatu searched for work all night; and Brendon Leonard edged his halfback rival Andrew Ellis.
The win puts the Chiefs on 40 points and reliant on one team behind them losing over the course of weekend.
The Chiefs lost skipper Jono Gibbes to knee trouble before the kickoff, but took the early initiative, had the bulk of possession and territory.
Those used to seeing the Crusaders stamp their authority early would have been rubbing their eyes.
The Chiefs were patient and played smart rugby, forced the Crusaders into damage limitation.
The Crusaders lineout was shabby, they fell off a whopping 13 first half tackles - a notable, if unusual culprit being McCaw, who copped one massive fend from Lauaki - and it was not until the second half that they hinted at their usual authority.
They did demonstrate how dangerous they can be with a breakout 70m try against the run of play after 27min, from a botched Chiefs throw-in. First five-eighths Stephen Brett whizzed through a gap, McCaw and Mose Tuiali'i made big ground before Tuiali'i flipped the final pass to lock Ross Filipo.
Earlier the Chiefs had created chances on both flanks. They got their own fine try when Lauaki surged forward, Muliaina grubber kicked superbly for Sivivatu to run on to, gather, swivel and dive across for his first try.
They were tested after the break, but they had laid the platform and weren't about to give any ground as they successfully held what they had gained.
Chiefs 30 (S. Sivivatu 2 tries; S. Donald 6 pen, con)
Crusaders 24 (R. Filipo, R. McCaw tries; S. Brett 4 pen, con). HT: 20-13