POCO Dorado seems invincible as a Wentworth Park stayer and the John Finn-trained greyhound is all the rage to extend her 720m tally there to eight starts for eight wins in Saturday night's Free-For-All.

Rarely has Sydney seen a long-distance greyhound like Poco Dorado, who usually jumps in front, leads at the first turn, "breaks up'' the field in the middle stages and then gets to the winning post powerfully.

Poco Dorado who has always performed best when drawn wide, has box six on Saturday, where her toughest opponent is expected to be rookie stayer Little Digger, perfectly positioned in box one.

But while Little Digger has won nine 520m races at Wentworth Park he has not been tested beyond 618m, having won over that trip at Richmond on October 26 in a sizzling 35.53sec.

After recording seven successive long-distance wins at Wentworth Park, including victory in the $75,000 to the winner Sydney Cup on October 20, Poco Dorado stepped out over 520m at headquarters last week and came from last at the first turn to win easily in smart time.

When she led throughout in the Sydney Cup, Poco Dorado exited box seven and covered the 720m in her personal best time of 41.68, just .15sec outside Xylia Allen's course record set on April 12, 2014.

Poco Dorado's litter brother and kennelmate Blue Moon Rising made a spectacular Wentworth Park 720m debut last Saturday, leading throughout to win a heat of the Ladbrokes Monthly Medal in a blistering 42.25sec.

The other heat was taken out by Irinka Leanne in 42.81sec, so Blue Moon Rising will be all the rage for Saturday night's final, despite drawing awkwardly in box six.

His toughest rival looms as Kanzan, who has clocked 42.16sec at Wentworth Park and who was not suited by box eight when a distant third to Blue Moon Rising last week.

"Kanzan has been knocked around a lot in her races and I'm hoping the move to an inside box will enable her to be up closer to the early lead on Saturday,'' trainer John Smart said.

"She is really fit because I trialled her over 366m at Appin on Tuesday and she clocked 21 seconds flat, a very good run for her.''

Meanwhile a slick post-to-post trial at Wentworth Park on Tuesday has Nangar Blaze poised to break through for his first win at headquarters in Saturday night's Ground Dog Day Vi Classic Stakes, a 520m fifth grade.

Nangar Blaze, trained by Mick Hardman for owner Ray Tanti, has not raced at Wentworth Park since September but trialled well this week.

"I took him to Wenty on Tuesday and slipped him from winning post to winning post and he clocked 24.27, which is very smart,'' Hardman said.

"He has box six on Saturday and while having box five vacant will help Nangar Blaze, I am a bit concerned about his litter sister and former kennelmate Nangar Gift being drawn outside him in box seven.

"Nangar Gift has early speed and tends to head to the rails so I hope she does not put her brother out of business in the run to the first turn.

"If Nangar Blaze can avoid his sister I am confident he will win.''

Outstanding provincial sprinter Flying Ella, who has won 13 of 25 races on out-of-town tracks, makes her Wentworth Park debut in Saturday's Ladbrokes Cash In Stakes, a 520m fifth grade.

Flying Ella has box six but trainer Darren Sultana is confident she will cope with her wide draw.

"She tends to run in a straight line from the boxes to the first turn,'' Sultana said.

"Although Flying Ella has not done it recently, in the past she has been capable of coming out like a missile so hopefully she will do that on Saturday.''

Best Bet Poco Dorado (race 5)

Best Value Kanzan (race 4)

Quaddie race 5 - 6, 1

Race 6 - 6, 1, 4

Race 7 - 6, 2, 8

Race 8 - 7, 8

$20 for 55.55%