A lot has been changing in the Bay area since the San Francisco 49ers and Jim Harbaugh “mutually parted ways” and now another unexpected star’s reported retirement will really affect the defense.

Yahoo Sports reported Monday that sources have said linebacker Patrick Willis is set to retire. Multiple media outlets have also said that the 30-year-old’s surprise decision will be announced on Tuesday.

This is another example of the many Niners players who have been departing from the team.

Pro Football Talk noted that running back Frank Gore is reportedly leaving to sign with the Philadelphia Eagles and wide receiver Michael Crabtree and guard Mike Iupati are not expected to re-sign.

In addition to possibly losing Willis to retirement, another blow to the defense is that lineman Justin Smith is also thought to be retiring.

Smith, 35, began his career with the Cincinnati Bengals and has been playing for the Niners since 2008. He was selected to the Pro Bowl five times and has more than 40 sacks with each team.

Willis spent his whole career with the 49ers after he was drafted in the first round of the 2007 draft. He has been voted to the Pro Bowl seven times and has been a defensive force that the team will surely miss if he hangs up his jersey for good.