Activate the updated Underdog promo code TOPACTION today, Friday, March 13, 2026 to receive $50 in fantasy bonus entries. To unlock the offer, new users only need to place a $5 or larger entry on NBA DFS picks, though the promotion can be used on entries for any available sport.
Take advantage of one of the top DFS sites in North America by using the sign-up module above. Once registered, you can start making predictions on Cavs vs. Mavs (7:30 p.m. ET on Prime Video) or any other NBA matchup on the slate.
| Underdog Promo Code TOPACTION | Underdog Available States |
|---|---|
| Play $5, Get $50 Fantasy Bonus Entries | AL, AK, AR, CA, DC, FL, GA, IL, IN, KS, ME, MS, MN, NE, NM, NC, ND, OK, OR, RI, SC, SD, TX, VT, VA, UT, WI, WY |
What Are the Underdog Promo Code TOPACTION Sign-Up Steps?
The steps you must follow to register with the new Underdog promo code TOPACTION are listed out below:
- Use the following link to sign up with Underdog as a new user today
- Create a username and password, and enter your prompted personal identifying information as prompted by Underdog.
- Enter the Underdog promo code TOPACTION in the appropriate field to get enrolled in the enhanced $50 new user bonus.
- Accept the Underdog Terms of Use and Privacy Policy, which confirm you're at least 18 years old (19+ in Alabama/Nebraska, 21+ in Massachusetts/Arizona).
- Make your first deposit with your preferred payment method of at least $10.
- Place your first qualifying entry of $5+ and wait for it to settle as a win or loss. After it grades, Underdog issues you $50 in fantasy bonus entries.
Make These Cavs vs. Mavs Predictions on Underdog Today
I found three Cavs vs. Mavs DFS picks on Underdog I like and included them below. Feel free to use any of these predictions in your own DFS entry today, Friday, March 12, 2026.
1. Cooper Flagg Higher Than 11.5 Rebounds + Assists
Flagg is the Mavericks' best player by a wide margin. While the Cavaliers may prove to be a tough matchup on the boards for Flagg, his height and playmaking ability should be enough to exceed 11.5 rebounds and assists. Find this and many other Flagg DFS markets when you register with the Underdog promo code TOPACTION.
2. Donovan Mitchell Higher Than 28.5 Points
Mitchell ranks seventh in the NBA in scoring at 28.4 points per game. He has a favorable matchup tonight, as the Mavericks rank 22nd in scoring defense. With James Harden flanking him and helping to set up shots, I like Mitchell to have a big game. Use the Underdog promo code TOPACTION if you want to place this prediction.
3. James Harden Higher Than 8.0 Assists
Since Harden was traded to the Cavaliers, his playmaking has been impressive. He still scores at a respectable clip, but his role has primarily been that of the primary ball handler as Mitchell's second fiddle. Since the Mavericks aren't a good defensive team, I anticipate Harden dishes out a healthy number of assists.
Sign up with the Underdog promo code TOPACTION and place the three NBA DFS picks above into a lineup. Put down $5 or more on your lineup and unlock $50 in fantasy bonus entries, win or lose.
Underdog Daily Promotions: Friday, March 13, 2026
Underdog provides returning customers with a bounty of promotions on a daily basis. Once you utilize the Action NetworkUnderdog promo code TOPACTION, you get access to these deals today:
- 40% Profit Boost: Make up to a $50 entry of Underdog picks on any sport and boost your potential winnings by 40%. Your entry must have between three and eight legs.
- Refer a Friend: Utilize the Underdog referral promotion and get $10 in bonuses once they register their new DFS account.
Terms & Conditions
Must be 18+ (19+ in AL, NE; 19+ in CO for some games; 21+ in AZ, MA, and VA) and present in a state where Underdog Fantasy operates. Terms apply. Offer not valid in MD, MI, NJ, NY, OH, and PA. Concerned with your play? Call 1-800-MY-RESET or 1-800-GAMBLER or visit www.ncpgambling.org. NY: Call the 24/7 HOPEline at 1-877-8-HOPENY or Text HOPENY (467369).
