With LDS Church President Thomas S. Monson’s death, Russell M. Nelson, the longest-serving Mormon apostle, is expected to step into the role of the faith’s prophet any day now.

Nelson’s elevation will surprise no one — for more than 170 years, that has been the Mormon sequence of succession.

What is in question, however, is which men the 93-year-old Nelson will choose as his two counselors in the governing First Presidency.

Thus, the LDS speculation game — some members jokingly call it “Mormon horse racing” — already has begun.

Will Nelson retain his predecessor’s two counselors, Henry B. Eyring and Dieter F. Uchtdorf?

After all, they proved instrumental in running the nearly 16 million-member Church of Jesus Christ of Latter-day Saints once Monson became incapacitated by age-related health concerns.

Dropping counselors would be a break with long-standing tradition. Such a move has happened in the faith’s history, but not for decades.

Monson’s immediate predecessor, Gordon B. Hinckley, made an unusual choice in selecting Eyring, then a junior member of the Quorum of the Twelve Apostles, to join him in the First Presidency.

Monson followed Hinckley’s action by dipping down even further into the Twelve, to tap Uchtdorf, a charismatic German and among the first non-Americans in the quorum.

(Steve Griffin | The Salt Lake Tribune) President Dieter F. Uchtdorf speaks during funeral services for LDS Church President Thomas S. Monson at the Conference Center in Salt Lake City on Friday, Jan. 12, 2018.

Removing Eyring, 84, and Uchtdorf, 77, from the First Presidency and returning them to their respective places in the Quorum of the Twelve could send shock waves throughout the church, especially given Uchtdorf’s widespread popularity.

Still, Nelson could revert to a pattern of the past and bring into the Big Three the most senior apostles after him — Dallin H. Oaks and M. Russell Ballard.

The new president could pick Oaks, who is a spry 85, as a way of preparing the former Utah Supreme Court justice to lead the church someday. Many counselors, including Hinckley and Monson, later ascended to the top post.

The prophet-to-be may opt just to leave Oaks in place and have him serve, as Nelson himself did, as president of the Quorum of the Twelve Apostles.

Still, some LDS presidents were never counselors — including Spencer W. Kimball, Ezra Taft Benson and Howard W. Hunter.

(Steve Griffin | The Salt Lake Tribune) President Russell M. Nelson smiles up at members of the Tabernacle Coir as he enters the Conference Center with the leadership of the LDS Church during funeral services for LDS Church President Thomas S. Monson at the Conference Center in Salt Lake City on Friday, Jan. 12, 2018.

For instance, Nelson, called as an apostle on the same day as Oaks in 1984 (but ordained a month before him), has never served in a First Presidency.

The former heart surgeon could choose Oaks, but leave Ballard, 89, as “acting president” of the Quorum of the Twelve Apostles, and add Jeffrey R. Holland, 77, as second counselor.

Holland, like Oaks, was president of LDS Church-owned Brigham Young University, and is a popular speaker among millennials.

Nelson also could reach deeper into the quorum and call David Bednar, who at 65 is among the youngest apostles. Bednar, a former president of BYU-Idaho, might appeal to a younger crowd, injecting enthusiasm and energy into the presidency. Or the former heart surgeon could tap a medical pal, former cardiologist Dale G. Renlund, 65, the newest apostle.

However, no rules require Nelson to choose a sitting apostle.

He could settle on Frenchman Gérald Caussé. As presiding bishop, overseeing the church’s extensive business and real estate holdings, Causse would bring vast knowledge of faith’s global operations.

Then again, First Presidency counselors don’t even have to be current LDS general authorities.

President Heber J. Grant, who governed the church from 1918 to 1945, sidestepped the LDS hierarchy altogether in his 1933 appointment of J. Reuben Clark as his second counselor. Clark had not served a proselytizing mission, nor had he ever been a bishop or stake president, but as U.S. ambassador to Mexico, he was one of Mormonism’s most prominent members.

The modern equivalent of Clark would be, of course, none other than 70-year-old Mitt Romney — who ran twice for U.S. president and is considering a bid for Orrin Hatch’s soon-to-be-vacant Senate seat.

This Mormon guessing game — for that’s all it truly is — probably will end almost as soon as it began.

With Monson’s funeral over, Nelson is likely to name his counselors within days at the same time his own presidency is announced. If he does choose a counselor from the Twelve, that will create another opening in that body, There is already one vacancy after the October death of Robert D. Hales.

Unless the name of a new apostle — or two — is divulged at the time of Nelson’s appointment, Mormons will begin a new round of “who will it be?”