Looking over the field for today's running of the Kentucky Derby one is impressed with the recent form of Alydar, winner of his last four races. The son of Raise A. Native is ready for the race of his life while there is some question as to the sharpness of his main challenger, Affirmmed, last year's 2-year old champion.

The big question is, is Affirmed sharp enough to whip Alydar.

Trainer Laz Barrera is supposed to know his way around the track. Affirmed won four races in as many tries in California but was not as impressive there as Alydar was in Florida and Kentucky. In his next to last race Affirmed whipped Think Snow by nine lengths. The comment in the Racing Form was "handily." In his last race, the Hollywood Derby, Affirmed beat Think Snow by two lengths and the comment was an ominous "driving."

So what does Barrera do? He stops on Affirmed, giving him only gallops until April 29 when he breezed him 1 1/8 mile in 1:56 1/5, trotting horse time for his caliber of horse. But, Barrera had his rider "ask" Affirmed for speed the last eighth of a jile which he did in :12 1/5, unquestionally race horse time.

Then, in a most imaginative maneuver, Barrera worked Affirmed five furlongs Wednesday in a fine :59. After that work it became apperent what he was doing. Barrera knew that Affirmed was low in energy in california April 12. So he built his stamina with a slow breeze that had to carry him the 1 1/4 miles after the last eighth in :12 1/5. Having satisfied himself with his ability to run long, without having to expend much energy to do so, Barrera then showed his stuff. He worked Affirmed the five furlongs that should have him fairly screaming to run.

Alydar and Affirmed are dead even on their best races. The reason Affirmed whipped Alydar more than the beat him was that trainer John Veitch, a relative newcomer, decided to start the promising Alydar in a stake race. Imagine, a maiden in a stake race. Alydar never did get synchronized after that. His idiosyncracies were attributed to bullheadedness and slow learning. But experience has proved that every time a trainer tries to jump his conditions, like having a six-round fighter go 10 rounds instead of first going eight, the horse is never quite right for a long time. In the Laurel Futurity Affirmed appeared able to take Alydar even if they had gone around the track once more.

Since then, however, Veitch has not made a wrong move. His give and take of energy with Alydar has been perfect. Even his final half-mile breeze of Alydar in :50 was exciting since his charge had won the Blue Grass by 13 lengths the week before.

So we find the two top colts coming up to the Derby at their best. It is up to the riders to finish the job.

Steve Cauthen is something special. A simple shake of the hand with the 18-year-old leaves one with an eerie feeling. The hands are long and strong, yet gentle. The youngster knows that he has to lay off the quality of speed of horses like Believe It and Sensitive Prince. Alydar nailed him in the Champagne when he elected to duel with several speed horses. He changed tactics in the Laurel Futurity.

Jorge Velasquez is a premier rider. His work with Alydar since he replaced Eddie Maple has been perfect. No doubt he will take back early and hope that Cauthen gets caught up in a battle for the lead with the pacesetters.

Believe It. and Sensitive Prince?

The former is at his very best despite suspicious wheels that appear to sting him at times. Maple lends further incentive for him to win. He should be third.

Sensitive Prince is undefeated and has the powerful finishing Micky Solomone as his rider. His record and latest work say he may be short of the top effort needed to whip the top two

Our selection: Affirmed, in a photo over Alydar.