"He is in Manchester for a medical" is the sentence that tells you a transfer is nearly done. It is also one of the least understood steps in the process, largely because clubs have no incentive to explain it.
What it is for
A medical is the buying club's last chance to find out what it is buying.
By this point the fee is agreed with the selling club and the personal terms are agreed with the player. The medical is the condition that remains, and it exists because a transfer fee buys a body as well as a contract.
What actually happens
It is not one examination. It is a battery, usually run in a few hours and sometimes across a day.
Imaging of known problems. Every player over about 22 has a history. The club scans the areas that history points at: the knee that was operated on, the hamstring that went twice, the ankle, the back, the groin.
Cardiac screening. An electrocardiogram and usually an echocardiogram. This is the part nobody negotiates over and the part with the gravest purpose.
Movement and strength testing. Range of motion, asymmetries between limbs, joint stability, sometimes force plate work. A club is looking for compensation patterns, meaning the ways a body has quietly rearranged itself around an old injury.
Bloods and general health. Routine, and occasionally the thing that finds something nobody was looking for.
The file. The buying club's medical staff read the player's history, which the selling club is expected to disclose. Non-disclosure of a known injury is a fertile source of subsequent litigation between clubs.
What clubs are really deciding
Not whether he is injured. The club usually knows that already.
The question is whether the player will be available for the proportion of matches the fee assumed, across the length of the contract being offered. A 27-year-old with a repaired knee might be a good signing on three years and a poor one on five, and the medical is where a club works out which contract to offer.
Which is why a medical can be passed and still change a deal.
What happens when it goes wrong
Three outcomes, in descending order of frequency.
The deal is restructured. The fee comes down, or more of it moves into add-ons, or the contract shortens, or the guaranteed money is cut. This is by far the most common consequence and it usually never becomes public.
The deal is delayed. The club asks for a second opinion or a further scan. A transfer that goes quiet for four days after the player arrived for a medical has often hit exactly this.
The deal collapses. Rare, and rarer at the top end, because the buying club has usually seen the file before the player is on a plane.
A signing who was already injured is a separate case and not a failure at all. Carlos Baleba was reported as injured while completing his move to Manchester United, with the earliest debut anyone named being 13 September, per this archive's transfer desk entry of 22 August 2026. Clubs sign injured players knowingly and price it in.
The bit that is theatre
Some of it is presentation. The scarf photograph, the tour, the club doctor's handshake. That is content, filmed for the announcement.
The substantive part happened in a scanning room with nobody watching, and its results are one of the most closely held documents at any football club.
The one-line version
The medical is not a pass or fail. It is the last repricing of the deal, held in private, on evidence the public never sees.
Sources: this archive's transfer desk entry of 22 August 2026, on the Carlos Baleba medical and injury status as reported by Fabrizio Romano and David Ornstein; this archive's glossary entry on the transfer medical.