SANTA CLARA – Reinforcements are on the way for the 49ers' lackluster wide receiving corps and a defense that finished Sunday's 34-3 victory over the Houston Texans without three starters.
Coach Jim Harbaugh said Monday the team's two rookie defensive linemen, Tank Carradine and Quinton Dial, are on track to begin practicing with their teammates for the first time next week. Harbaugh also said receiver Mario Manningham, who has been out since a December ACL injury, could begin practice next week and Michael Crabtree could be ready to play by mid-November.
Crabtree ruptured his right Achilles' tendon May 21 but has looked surprisingly spry during recent rehabilitation sessions with trainers.
Cornerback Eric Wright also is ready to begin practicing next week, Harbaugh said.
Those players are on various injury lists and don't count against the 49ers' 53-man limit. They can join practice from Oct. 15 through Nov. 19. Once a player begins practicing, the 49ers have three weeks to place him on the 53-man roster.
Harbaugh spoke before the results of Ray McDonald's MRI were available. The defensive end left Sunday's game after experiencing what he described as "a bee sting" in his right biceps. McDonald said he did not believe the injury was serious, but if he has to miss an extended period, the 49ers, who already lost nose tackle Ian Williams for the season because of a broken ankle, could use Carradine and Dial for depth.
Carradine, a second-round pick who injured his ACL in November, will play defensive end and is a candidate to be a long-term replacement for Justin Smith. Dial, who Harbaugh said was up to 340 or 350 pounds, will play nose tackle.
"Moving real well," Harbaugh said of Dial, a fifth-round pick. "So high hopes for him."
At wide receiver, the 49ers have had little productivity outside of Anquan Boldin, the only wideout who caught a pass in Sunday's win over Houston. Through five games, he has made 67 percent of the catches and produced 78 percent of the yardage by the wide receivers.
Manningham, the team's No. 3 wide receiver last season, could be back as early as the 49ers' Oct. 20 game at Tennessee. Harbaugh's timetable for Crabtree means he could be back for the Nov. 17 game at New Orleans.
McDonald wasn't the only starter who watched the end of Sunday's game from the sideline. Inside linebacker Patrick Willis missed his second consecutive game because of a groin injury. His replacement, Michael Wilhoite, had 11 tackles on defense and two on special teams.
"That's a highlight when a guy's playing full time on defense and making production in the special teams," Harbaugh said.
Willis was close to returning against Houston and likely will play against Arizona on Sunday. Harbaugh offered no timetable for the return of outside linebacker Aldon Smith, who is undergoing treatment following a DUI arrest last month, but Harbaugh said Smith is making progress.
"A few texts," Harbaugh said of his communication with Smith. "Just heard things are going very well; very positive reports back."
Read Matthew Barrows' blogs at www.sacbee.com/sf49ers and listen for his reports Tuesdays on ESPN Radio 1320.