Officers believe that the men were stabbed.
Emergency services were called to the area just after 8:30 pm and both men, who are in their 20s, were taken to hospital for treatment.
One man has since been discharged from hospital, the other remains in hospital in a serious but stable condition.
Detective Inspector Esther Scott said: “This incident happened in the street, while it was light. There are likely to have been a number of people walking and driving in the area.
“If you were in the area of Long Lane and Broom Leys Road - between 8-9 pm, and have any information regarding the incident, please come forward.
“Similarly, anyone driving in the area, please check your dashcam footage and contact the police if you have anything that could assist with our enquires.”
Scene preservation currently remains in place in Long Lane and no one has been arrested in connection with the incident.
Anyone with information is asked to call police on 101, quoting crime reference number 22*338737.
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