Lance Briggs Accused of Deadbeat Daddery

Lance Briggs -- who made more than $52 MILLION during his NFL career -- is accused of stiffing his baby mama to the tune of $37,000 ... this according to court docs obtained by TMZ Sports.

The woman behind the allegations is Sabina Chavez -- who has an 8-year-old daughter with the retired Chicago Bears linebacker.

According to court docs filed in L.A., Briggs had been ordered by an Arizona court to pay $9,100 per month in support.

But Chavez says Briggs ain't keepin' up his end of the bargain -- and by the end of August had only ponied up $8,100 of the $45,500 he owed. So she filed court docs asking a judge to force Briggs to pay up the remaining $37,400. A court date in the matter has not been set.

The relationship between Briggs and Chavez has been rocky for years -- they've been going back and forth in court battles since the kid was born.