The second provision would guarantee the full contract if Burleson is paid more on average per year than all of his team's running backs combined. At the time of his signing, the averages of the Vikings' tailbacks fell well shy of the $7 million average of the Burleson offer sheet. However in Seattle, running back Shaun Alexander alone made an average of over $7 million per year. In 2011, the NFL and NFLPA ratified a new collective bargaining agreement. In this agreement, poison pill clauses were eliminated from offer sheets issued to players under the transition tag. The specific language in the CBA states:  "No Offer Sheet may contain a Principal Term that would create rights or obligations for the Old Club that differ in any way (including but not limited to the amount of compensation that would be paid, the circumstances in which compensation would be guaranteed, or the circumstances in which other contractual rights would or would not vest) from the rights or obligations that such Principal Term would create for the Club extending the Offer Sheet (i.e., no 'poison pills')." The effect of this additional language has resulted in the transition tag being useful to teams again. In 2014, the Pittsburgh Steelers applied the transition tag to Jason Worilds and the Cleveland Browns applied the transition tag to Alex Mack. Worilds signed his transition tag, while Mack accepted an offer sheet from Jacksonville. Cleveland later matched to the offer sheet, thus keeping Mack as a Brown.