Horse Racing Multiple Tips: Trio to star at Kempton and Chepstow for 44/1 treble

• Conditions at Chepstow have come right for first pick of treble

• Progressive Mambo set to dance to Grade 2 success at Kempton

• Alan Dudman picks out a Saturday acca with three horses at 44/145.00

• Read all about Betfair's Christmas weekend free bet offer here

Chepstow - 13:05: Back Siam Park @ 5/23.50

The going has altered the arithmetic somewhat for Saturday and this 13:05 initially was one of the races I previewed in my ante-post column and liked the look of Rath Gaul Hill at a big price, but that won't be happening as he's a non-runner and the new pick of Siam Park is based on the current weather. 

The going could be fairly lively for Welsh Grand National Day at Chepstow, and while on Tuesday I displayed the fears for Siam Park as a good ground horse with form on good ground, he now scoops the position as the one to back following another dry week. 

As a six-year-old on the up, he has a bit more scope from his current mark as one of the youngest in the field and he handled the ground (officially good at Plumpton last time) very well. In fact, it was a personal best run over fences to score by nearly 5L back in trip. He has form over further, so Chepstow shouldn't hold any fears and he's a good jumper from the front, and those tactics are always a plus in Wales.

Siam to score please.

Kempton - 13:55: Back Mambonumberfive @ 2/13.00

What a day for Ben Pauling and Ben Jones, and Saturday might add some shine to yesterday's big Grade 1 in the Wayward Lad Novices' Chase with Mambonumberfive.

He's not the favourite here, but perhaps he should be. I liked his strong finishing effort at Newbury last time coming from off the pace to beat The Mighty Bandit, and the second has franked the form with a win since.

Mambonumberfive also landed a strong-looking 0-130 at Aintree in November, beating horses with form and in-form since, plus the third Glengouly has landed the December Gold Cup at Cheltenham for another boost.

Well worth a shot up in grade here, I'd have him favourite considering he won the Adonis here as a juvenile hurdler and track form around Kempton is never a bad thing and Pauling has a decent strike-rate around Kempton in the last five years at 20%. 

Chepstow - 14:10: Back Keable @ 10/34.33

Keable looked to need every inch of the 3m last time at Newbury and while the ground might pose a different sort of test, he looks a very strong stayer at the trip.

Santos Blue, the top weight, has plenty of form in soft and heavy, but his mark looks on the stiff side where as Keable gets a stone from him, which makes like tough for Santos Blue given Keable's progressive profile.

His attitude looks excellent too, a real tough nut, and having a runner more pugilist than poetic will do for this race. I also tend to think that Philip Hobbs (and Johnson White) tend to run nice hurdlers at this track, and this term are 3-14 at 21% here.

Now read more tips and previews for Saturday here!