Experience won out over an expensive price tag as Extra Time built on his stable's successful record in the National Stakes at Morphettville.

Fitted with blinkers at his fourth start, Extra Time travelled too keenly for veteran trainer Leon McDonald's liking but it made little difference to the result.

Extra Time ($7) mustered with natural speed after jumping well for jockey Jason Holder and led before finding a further gear to stride clear for a facile 3-1/2 length victory.

It McDonald's fourth win in the Group Three race for two-year-olds and it came with the added satisfaction of lowering a boom on the blueblood Kazuhiko.

Trained in Melbourne by Lloyd Kennewell, Kazuhiko ($4) was sent to Adelaide for a much-anticipated debut and he carried heavy support to start favourite before finishing second.

At $1.7 million, Kazuhiko was one of the most expensive yearlings sold in Australia last year as a son of legendary Japanese sire Deep Impact.

Kazuhiko settled midfield on the rail but lost the chance to test the winner after wandering about under riding from Zac Spain.

But the signs were encouraging from the 300m when Spain was able to get his mount to go straight and Kazuhiko warmed up generously at the end of the 1200m contest.

McDonald runs one of Adelaide's best stables in association with his son-in-law Andrew Gluyas and the veteran trainer said Extra Time had always shown promise.

"The horse has been racing really well without much luck ... I think the blinkers made all the difference to him," McDonald said.

"(Although) he looked to be a bit too keen to me, but by the time they got to the corner I sort of had a look back through the field and there were a lot of horses under pressure."