If 2.5M was fair value for a second year pro (even as talented as Martinez is), the WT budgets would be a lot higher than they are now.
Let's say that rider costs are hypothetically 80% of the budget. For a 25M budget team, 2.5M on a rider would be 12.5% of the rider cost total.
I don't know about other leagues, but in NHL for example, 12.5% of the current salary cap is superstar money (over 10M a year).
So I would say, either the 2.5M is made up, the valuation of a second year pro is way off (assuming a budget of around 25M), or the budget of a team making such an offer is substantially higher than 25M.