Clemmings, 26, is a former fourth-round pick out of Pittsburgh by the Vikings in the 2015 NFL Draft. He was in final year of his four-year, $2.804 million rookie contract when the Vikings waived him as they trimmed their roster down to the 53-man limit last year.
The Reskins claimed him off of waivers only to cut him loose at the start of the regular season a few months ago. Clemming was once again claimed off waivers; this time by the Raiders.
Oakland waived Clemming with an injury designation last week.
In 2018, Clemmings appeared in four games for the Raiders.
Cowser, 28, wound up going undrafted out of Southern Utah before signing a three-year, $1.62 million contract with the Raiders back in 2016. Unfortunately, the Raiders waived him with an injury designation and he later reverted to their injured reserve list after clearing waivers.
Oakland decided to cut him loose with an injury settlement before signing him to their practice squad and eventually promoting him to their active roster towards the end of the 2016 season.
Cowser returned to the Raiders this past April on a one-year exclusive rights contract but has been on and off of their roster.
In 2017, Cowser appeared in all 16 games for the Raiders and recorded 23 tackles, a forced fumble and two recoveries.