SANTA CLARA – Let the games begin. Well, not officially for a few months, but the 49ers’ game-within-the-game position battles now commence.

Organized team activities begin Monday, and these ramped-up practices offer a first look at the most promising roster battles in coach Kyle Shanahan’s three years.

Here are five players or groups under the most scrutiny:

1. Is Jimmy G’s knee A-OK?

Don’t dare let fatigue set in when it comes to reports about Jimmy Garoppolo’s knee rehabilitation. More of the same is coming every week and every month until, well, it becomes unnecessary.

A day after OTAs begin, the media is allowed entry Tuesday for the first chance to see Garoppolo throw – with his right arm, not his repaired left knee, mind you – and he won’t have to be side-stepping Dee Ford or Nick Bosa at full speed.

Heck, this will be the first time he’s been seen throwing a football since his Sept. 23 injury at Kansas City, assuming the 49ers indeed let him toss the ball in some drills while Nick Mullens and C.J. Beathard figure to work all 11-on-11 action.

Garoppolo said earlier this month he is “coming along well” in terms of throwing, running and cutting. Now come practices to help with his “reactionary stuff,” and everyone knows how well he fared in that capacity in the December To Remember (5-0, 2017).

2. Will Dante Pettis emerge as Year 2 star?

It’s been a few months since the 49ers brass advertised their desire for Pettis to break out in his second season the way tight end George Kittle did last year. Welp! Pettis certainly has room to improve and showed enticing skills as a rookie, starting just seven games and producing 27 catches, 467 yards and five touchdowns.

Pettis can use this final month to validate those Year 2 hopes. He won’t just be handed more opportunities. The 49ers will also turn up the heat on incumbents Marquise Goodwin, Kendrick Bourne and Trent Taylor. After all, rookies Deebo Samuel and Jalen Hurd, this year’s second- and third-round picks, also have entered the fray.

Goodwin, in fact, might be the most compelling receiver story. Is he ready to return to 2017 form, or if he’s truly destined for a specialty role, is he okay with that? Pettis could eat into his snaps. Game. Within. The. Game.

3. Any fantasy football rushers?

The 49ers are stocked at running back more than any other position, so snaps figure to be divvied up pretty equally these ensuing months. But who will look most capable of earning the biggest workload come Sept. 8 in Tampa? Shanahan loves to have so many choices.

Jerick McKinnon (above) might be slow-played into action as he comes off knee reconstruction. Tevin Coleman’s addition – and reunion with Shanahan, his former Atlanta Falcons muse – is especially intriguing. Matt Breida and Raheem Mostert are hungry to prove themselves, again.

In fantasy-football parlance, the 49ers have too many options, so any sign of stardom will be taken into serious account the next month.

4. How new and improved is pass rush?

Unquestionably the biggest offseason moves came in the 49ers’ most-needed department: pass rush. The OTAs will begin to unveil how intimidating Dee Ford (above)and Nick Bosa look on the edges as bookends to DeForest Buckner, Arik Armstead and Solomon Thomas.

“It’ll be interesting in practice,” Garoppolo said earlier this month. “But it will be good practice seeing those guys every day, D-Fo and those guys up front.

“It’s an impressive group and it will lead to good competition.”

Ah, yes, competition. Aside from the aforementioned five defensive linemen, fierce battles should ensue among the reserves, particularly Ronald Blair, Kentavius Street, Jullian Taylor, Sheldon Day and Cedric Thornton.

5. Any cornerstone cornerbacks?

The 49ers secondary could look vastly different a year from now. Everyone seemingly is on a one-year tryout, whether it be young players trying to prove their worth or veterans showing they’re healthy enough to make a play. Reminder: zero interceptions last year by the cornerbacks.

Related Articles George Kittle just might return from knee injury vs. Giants despite MetLife field concerns

Jimmy Garoppolo’s injury may reveal a flaw with NFL officials’ face masks

NFL: 49ers can’t escape from New York’s MetLife Stadium turf

How 49ers’ Nick Mullens set himself up for unfair expectations

The Deets: Kyle Shanahan will have to prove he’s a genius against the Giants Every defensive back should benefit from an improved pass rush, so that excuse is off the boards. A healthier Richard Sherman (above) should bode well on the left side. As for the right side, Jason Verrett is a leading candidate to start, even though he acknowledged last week on SiriusXM NFL Radio that he considered retiring before the 49ers beckoned him after three injury-plagued years.

Ahkello Witherspoon is looking to get over his sophomore slump. Tarvarius Moore is one year into his conversion from safety. Intercepting a Garoppolo pass could do wonders for any cornerback (just not for Garoppolo’s sake).