As noted in here, #Giants did in fact use signing bonuses for their top FAs. They quickly amended the original structure to deals for James Bradberry ($9M signing bonus, $3M roster bonus) + Blake Martinez ($6M signing, $4M roster). Provides more cap space than has been reported.
Converting large chunks of cap into signing bonuses has allowed Big Blue to clear some room in case they want to go after another talented free agent.
ESPN’s Field Yates stated that the Giants have nearly $20 million in cap available, which would open up the opportunity for them to retain Markus Golden on a reasonable deal.