Kelly, 24, is a former first-round pick by the Colts in last year’s NFL Draft. He is entering the second year of a four-year, $10.45 million rookie contract and is set to make a base salary of $925,045 and $1.4 million over the next two years.
In 2016, Kelly appeared in all 16 games for the Colts and ProFootballFocus rated him as the No. 32 overall center out of 35 qualifying players.
Bostic, 26, is a former second-round pick of the Patriots back in 2013. After two years in Chicago, the Bears dealt him to the Patriots for a sixth-round pick that later became Jordan Lucas.
However, the Patriots elected to trade Bostic to the Lions for a conditional seventh-round pick in 2017 shortly after last year’s draft. Bostic played out the final year of his four-year, $3.941 million rookie contract before the Colts signed him to a one-year, $690,000 deal this past April.
Bostic will be an unrestricted free agent again next year.
In 2017, Bostic appeared in 14 games for the Colts and recorded 97 tackles, one sack, a fumble recovery and three pass defenses. Pro Football Focus has him rated as the No. 40 linebacker out of 92 qualifying players.