UFC Fight Night 91 - McDonald vs. Lineker --- UFC 201 - Lawler vs. Woodley 
UFC on Fox 20: Holm vs. Shevchenko is an upcoming mixed martial arts event that will be held on July 23, 2016 at United Center in Chicago, Illinois.
Official fight card
Main Card (Fox)
Women's Bantamweight Holly Holm vs. Valentina Shevchenko
Lightweight Edson Barboza vs. Gilbert Melendez
Heavyweight Francis Ngannou vs. Bojan Mihajlovic
Women's Strawweight Felice Herrig vs. Kailin Curran
Preliminary Card (Fox)
Bantamweight Frankie Saenz vs. Eddie Wineland
Featherweight Darren Elkins vs. Godofredo Pepey
Welterweight Kamaru Usman vs. Alexander Yakovlev
Lightweight Michel Prazeres vs. J.C. Cottrell
Preliminary Card (UFC Fight Pass)
Welterweight Alex Oliveira vs. James Moontasri
Featherweight Jim Alers vs. Jason Knight
Heavyweight Luis Henrique vs. Dmitry Smoliakov
Background
The event is expected to be headlined by a women's bantamweight bout between former Boxing and UFC Women's Bantamweight Champion Holly Holm and multiple-time Muay Thai world champion Valentina Shevchenko.
A bout between former UFC Light Heavyweight Championship challengers Anthony Johnson and Glover Teixeira was expected to serve as the co-main event. However, Johnson pulled out on June 18 to tend to personal issues. In turn, promotion officials elected to pull Teixeira from the card and the pairing was left intact and rescheduled to take place four weeks later at UFC 202.
Ryan LaFlare was expected to face Alexander Yakovlev at the event. However, LaFlare was removed from the fight in early June after sustaining an undisclosed injury and replaced by The Ultimate Fighter: American Top Team vs. Blackzilians winner Kamaru Usman.
Tony Martin was expected to face Michel Prazeres at the event. However, Martin pulled out on July 6 due to a neck injury and was replaced by promotional newcomer J.C. Cottrell.
George Sullivan was expected to face Héctor Urbina, but was pulled from the event due to a "potential compliance issue" with the UFC's anti-doping policy stemming from "voluntarily disclosed information" he provided to USADA. Urbina will still weigh in as a potential backup opponent should there be a need for him to compete in another bout. Otherwise, he will be re-booked for another card in the near future.