If you’re playing the $21,000 Lucky 7s promotion over the next seven Friday nights at TwinSpires.com then the phrase that pays is Return on Investment (ROI) because that is how all the scoring is done.

Picking winners on Australian races is always a fun challenge because of the full field and competitive races, but when it comes to ROI contests it’s not how often you’re right but how right you are since one big pay day could be worth more than a few favorites.

To qualify for the TwinSpires.com Lucky 7s contest, you must bet $21 on each Group 1 race. For this week that means Newmarket Handicap at 11:20 p.m. ET from Flemington, the Norton Stakes at 11:30 from Warwick Farm and the Darley Australian Cup at midnight from Flemington.

There are three tiers of prizes: The best ROI, any ROI above 210% and any ROI above 70% (but lower than 210%). That means the target gross is $107.10 to cash something, meaning one 15-to-1 winner would do it, but we’ll look at some exacta plays as well to try to go for bigger prizes!

In the Newmarket, the Group 1 winners among the 15 entries going six furlongs are Moment of Change, Lankan Rupee, Samaready, and Shamexpress, and only the latter two accomplished the feat at this distance with Shamexpress defeating Moment of Change in this race last year and Samaready a two-time winner under these conditions. I prefer both of them to Moment of Change, who seems to prefer longer and Lankan Rupee who might be tested the longer he goes.

Both Samaready and Shamexpress both shed weight from previous top efforts, and angle that could also benefit longshot Pago Rock, who has no races with an impost less than 126 pounds on his PPs but totes 117 here, and his local preps for this off a summer (Southern Hemisphere seasons, yo!) layoff could get in the mix with any improvement.

Lucky 7s strategy: $7 to win on Samaready, Shamexpress, and Pago Rock

Pari-mutuel wagering strategy: Pago Rock across the board at 10-to-1 or better and an exacta key box with the Group 1 winners.

The Norton Stakes is the middle leg of the Group 1 treble and features the most likely shortest price and shortest field of the trio with It’s a Dundeel taking on eight others going one mile in a race he won last year.

The question on whether you want to take a short price on this one is if you think his comeback race—basically a six-furlong trial—off a four-month layoff was enough to get him back to top form, which probably does win this, but Boban has been racing steadily all season and gets back to the mile distance that earned him his Group 1 last year at Flemington.

Lucky 7s strategy: $7 exacta It’s a Dundeel with Boban twice ($14 total, but you must place the bet two times for $7 to count) and $7 to win on Boban.

Pari-mutuel strategy: Bet It’s a Dundeel to win at 2-to-1 or better. Bet Boban across the board at 3-to-1 or better. Use both and no one else in multi-race wagers.

The Darley Australian Cup is the showpiece event of the evening at 1 ¼ miles, and while 2013 Melbourne Cup winner Fiorente is a clear favorite, a pair of three-year-olds will take action against their elders: Shamus Award and Thunder Fantasy.

Whether a Melbourne Cup winner gets bet in the States as much as a returning Breeders’ Cup Classic winner would remains to be seen, but I do think we’ve seen enough from Shamus Award—already a Group 1 winner at 1 ¼ miles—to view him as a threat at more generous odds, and he defeated Fiorente last year when in receipt of 21 pounds in the aforementioned Group 1 score. He gets 10 pounds this time.

Thunder Fantasy has a few more questions, but you do get a few more dollars. He couldn’t catch gate-to-wire winner Shamus Award last time, but the front-end waters could get deep here going longer with Mourayan and Star Rolling both possible threats early.

Lucky 7s strategy: $7 to win on Shamus Award and $7 exactas Shamus Award over Fiorentine and Thunder Fantasy.

Pari-mutuel strategy: Shamus Award to win at 3-to-1, Thunder Fantasy to win at 5-to-1 and them in an exacta over Fiorentine.