Coomer called it a lie.
Looking at the photo, McFarland asked Swift why the front of her skirt did not appear to be lifted.
Taylor has said if she gets compensated by money, she will donate it to a charitable cause that fights sexual assaults against women.
During the trial of a case that is closely watched by sexual abuse activists, Taylor cracked a joke about the alleged incident that cost Mueller his job.
The 27-year-old pop star is countersuing the DJ.
She also rejected the assumption that she misidentified Mr Mueller, saying: "I'm not going to allow you or your client to say I am to blame".
Swift testified, "He did not touch my rib".
When questioned by Mueller's lawyer, Gabriel McFarland on the incident, Taylor stood by what allegedly happened, including Mueller grabbing her "bare bottom". Swift's bodyguard and Simbeck are listed as potential witnesses. During a 2013 concert in Denver, a DJ called DJ David Mueller posed for a photo with Taylor and his girlfriend. "We are a big group of creative woman who are supporting her as an artist and we love what she does", she said.
To this Swift replied, "Your client could have taken a normal photo with me".
The photo of Swift, Mueller and Melcher was not publicly released, but was shown to the eight-member jury during opening statements, according to The Associated Press.
Swift is counter-suing Mueller for a symbolic $1 (77p) in compensation, and says she wants it to serve as an example to women who have been assaulted. She added, "He stayed latched on to my bare ass...as I moved away from him visibly uncomfortable..."
According to the lawsuit, Swift claimed that David Mueller, who was sacked from KYGO pursuant to Swift's allegations, groped her during a pre-show meet & greet event.
Taylor's attorneys believe the photograph is a "damning" proof of Mueller touching the singer-songwriter inappropriately.
She claimed her photographer witnessed the incident and took a picture of it.
His testimony came a day after Ms Swift took the stand to describe the incident, calling it a "definite grab". She testified that Swift later told her what happened, looked at a photo and pointed out Mueller as the person responsible.
The alleged assault is said to have occurred in 2013, during a Denver stopover on Taylor Swift's Red tour.
Testimony has resumed in a civil trial over whether Taylor Swift was groped by a former radio DJ. "We absolutely wanted to keep it private, but we didn't want him to get away with it". Swift's side has claimed that Mueller is only suing her for the money and fame it's affording him while Mueller's attorney argues that Swift is ruining his career with her "false" claims.