Heffernan has high hopes of nailing O'Brien record on The Pentagon

The jockey who has been with Aidan O'Brien through thick and very little thin would love nothing more than to provide him with a world-record 26th Group 1 strike in the Racing Post Trophy, he stressed on Friday.

Seamie Heffernan, a linchpin of O'Brien's Ballydoyle operation for 21 years, has been entrusted with the mount on Investec Derby joint-favourite The Pentagon in Saturday's showpiece at Doncaster, where his boss is a 4-7 chance with William Hill to notch the top-level triumph that will take him clear of Bobby Frankel.

Ryan Moore delivered O'Brien's 25th top-level winner in the calendar year at Ascot last weekend aboard Hydrangea, and while he is on favourite Saxon Warrior at Doncaster, Heffernan's mount The Pentagon is no bigger than 5-1 and will have plenty of supporters.

His jockey is one of them, saying: "It's great we're getting another run into The Pentagon and hopefully he'll show the ability we know he has in such a prestigious race.

"It would mean a lot to me if I could win the Racing Post Trophy for the first time and break the record for Aidan."

Heffernan, 45, has been a key cog in the O'Brien machine as number two to Mick Kinane, Johnny Murtagh, Jamie Spencer, Kieren Fallon, Joseph O'Brien and now to Moore and, even as understudy, has ridden 29 Group 1 winners – only one of which was not for Ballydoyle. He has contributed three this year.

Group 3 scorer The Pentagon is 10-1 joint-market leader for the 2018 Derby with unbeaten Beresford Stakes winner Saxon Warrior, whose only two outings have come since we last saw The Pentagon, and it is that lack of recent race-fitness that may have swayed Moore towards Saxon Warrior.

Heffernan, who rides The Pentagon in his work, added: "We've always thought plenty of him, but he hasn't run since winning the Tyros Stakes at Leopardstown in July, whereas the other three Ballydoyle runners have had more recent runs.

"Whatever the outcome on Saturday, The Pentagon is certainly one to look forward to next year."

The other O'Brien runners in a field of 12 for a race he has won seven times are Seahenge (Donnacha O'Brien) and Coat Of Arms (Wayne Lordan), with the Jim Bolger-trained Verbal Dexterity splitting Saxon Warrior and The Pentagon at the head of the market.

Also among those trying to prevent the O'Brien landmark success is Roaring Lion, winner of the Royal Lodge Stakes, and Chilean, whose rider Andrea Atzeni is bidding for a fifth consecutive Racing Post Trophy success.

Coral spokesman David Stevens said: "With four runners, including two of the first three in the betting, Aidan O'Brien is odds-on to win the Racing Post Trophy and overtake Bobby Frankel's record of 25 Group 1 wins in a year, an outcome that has looked inevitable for several weeks now."

The going at Doncaster on Friday remained good on the straight course, good, good to soft in places, on the round course. Clerk of the course Roderick Duncan reported there had been no measurable rain and the forecast was for it to be dry and bright.

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