The flag reported by Juan Carlos is a ~2:3, white and purple unequal symmetric horizontal triband (approx. 1+3+1), with the club’s logo on the middle stripe and the words "Deportes Concepcion" (sic, instead of "Concepción") wide set in serifless purple bold capitals centered on each of the white stripes.
The logo is round (on the flag its diameter ~3/8ths of the flag’ height) showing a lion head on a white football ball with purple stitching surrounded by a wide purple ring with white edgings reading, again, "Deportes Concepcion" (sic, instead of "Concepción") set in serifless purple heavy bold capitals with round bullets separating the two words, which are both readable from the upright position.
Club Deportes Concepción is a Chilean football club based in the city of Concepción. The club was founded on 29 February 1966 by the organizations of several amateur clubs such as Galvarino, Liverpool, Juvenil Unido, Santa Fe, and Club Lord Cochrane.
Esteban Rivera, 23 March 2014
The English Wikipedia article also says that "in 2016 the club was expelled of the Chilean National League system due to economic problems." António Martins-Tuválkin, 20 May 2017
The exact shade of purple seems to vary: the first graphic above is lavender and matches Juan Carlos’ original image, as well as the usual kit color; the second graphic is a stronger shade of purple, and matches the usual coloring of the club’s emblem. António Martins-Tuválkin, 20 May 2017