49ers defensive lineman Alfred Collins’ injury latest blow to largely unproven unit

The San Francisco 49ers‘ defensive line suffered another major blow on Tuesday.

Second-year defensive lineman Alfred Collins tore his patellar tendon at the team’s second practice in Melbourne, coach Kyle Shanahan announced Wednesday. Collins will be out for the season.

Collins’ injury comes a week after defensive end Sam Okuayinonu broke his foot and was placed on injured reserve. 

Defensive line is by far the biggest concern for San Francisco’s defense entering the season – it is both injured and wildly inexperienced. In addition to Collins’ and Okuayinonu’s injuries, Nick Bosa and Mykel Williams are coming off torn ACLs. Bosa will play in Week 1, while Williams will begin the season on the reserve/PUP list. Undrafted defensive tackle James Thompson Jr. didn’t participate in Tuesday’s practice.

The 49ers’ healthy defensive tackles entering Week 1 are Osa Odighizuwa, CJ West and Gracen Halton, while they will likely promote a practice squad player on Thursday. At defensive end, San Francisco will trot out Bosa, Keion White, Romello Height and Khalid Kareem.

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This article originally published at 49ers defensive lineman Alfred Collins’ injury latest blow to largely unproven unit.