Brock Purdy has dealt with injuries this season. The one-time Pro Bowler suffered a left shoulder and toe injury in his side's opening game against the Seattle Seahawks. The toe injury saw him miss the team's Week 2 game against the New Orleans Saints.With the San Francisco 49ers facing off the Arizona Cardinals in Week 3, let's look at Purdy's availability.Is Brock Purdy playing this week?No, Brock Purdy is not playing this week. San Francisco 49ers coach Kyle Shanahan has ruled out the Iowa State product from the upcoming game. Mac Jones is set to start in his place for the second straight game."I think it is highly unlikely that he will start," Shanahan said Friday, per ESPN. "We are just trying to see where he is at to see if he can be a (No.) 2 or an emergency (No.) 3."However, Purdy seems eager to get back on the gridiron, and he's doing his best to prove his fitness."I want to play every game," Purdy said on Thursday. "I want to be out there. You only get 17 regular-season games, and every game matters, especially a divisional (game) going against the Arizona Cardinals. If you ask me, I would love to, but I am trying to be smart with my body here."Mac Jones looks all set to play in Week 3, and he'll look to continue his impressive form from Week 2. The former New England Patriots standout amassed a stat line of 279 passing yards and three touchdowns in the win over the Saints. It ensured that the 49ers maintain their unbeaten start to the season.How has Brock Purdy performed this season?Brock Purdy started the game against the Seattle Seahawks in Week 1 and led the 49ers to a win. The former Mr. Irrelevant amassed a stat line of 277 passing yards, two touchdowns and two interceptions in the opening weekend victory.However, injuries sustained in that game meant that Purdy would miss out on the second game of the campaign. He watched on as Mac Jones led the 49ers to a win over the Saints to improve their record to 2-0. Jones looked at home in Kyle Shanahan's offense.Brock Purdy performed decently in his only game of the season thus far. However, he's currently on the sidelines recuperating from a nagging injury. While it's unlikely that he features against the Arizona Cardinals in Week 3, there's a good chance that he'll be fit enough to play in the subsequent weeks.