INDIANAPOLIS – Free agency will fill some holes in the Vikings' roster. But there still will be missing pieces, and General Manager Rick Spielman should have a better idea, after free agency, what he is looking for in April's NFL Draft.

That draft should be strong at offensive tackle and cornerback, and that might affect decisions about rebuilding the Vikings' secondary or offensive line.

Receiver is the consensus deepest position, but analysts, coaches and executives have touted depth among top offensive tackles and cornerbacks billed as ready to immediately help teams. Spielman cautioned that the Vikings' needs could "significantly change" pending talks with representatives of pending free agents and high-priced veterans, including left tackle Riley Reiff and cornerbacks Xavier Rhodes, Trae Waynes and Mackensie Alexander.

Video (08:45) Ben Goessling and Andrew Krammer recap the week in Indianapolis, where the Vikings made initial approaches to free agency and the draft.

But with five pending free agents in the secondary, including three corners, the Vikings might be open to taking another cornerback in the early rounds, regardless of what they do in free agency.

"I'm sure we'll have to address it [in the draft]," coach Mike Zimmer said. "We've got a lot of decisions to make there in that back end, but that's part of the process we have to go through. If there's a great pass rusher there, it doesn't mean we won't [draft] him, or a great offensive guard or something like that."

This draft class is "really good" at cornerback, according to NFL Media analyst Daniel Jeremiah. Ohio State's Jeff Okudah will be gone early, and Florida's C.J. Henderson and Utah's Jaylon Johnson won't be far behind. One possible Day 2 option is a familiar name: Alabama cornerback Trevon Diggs, who at 6-1 is the type of big-bodied corner to replace Rhodes or Waynes.

"Some Aqib Talib-type skills," Jeremiah said. "The question is just pure deep speed, but real fluid. Obviously Stefon's brother there, the wide receiver with the Vikings. Former wide receiver, kickoff returner. Really skilled athlete."

When asked about the likely roster churn ahead for the Vikings defense, Zimmer referenced the first overhaul when he arrived in 2014 saying, "it was pretty ugly at that point." This week, coaches and scouts mined deeper into corners and safeties while Zimmer said he still sees upside in Mike Hughes, Holton Hill and Kris Boyd from the current roster.

"I don't know that we'll have an entirely new corners room," Zimmer said. "If it is that way, then we just have to do a good job keeping guys in there and making sure they can play and trying to help them as best we can. We're not going to cry because we don't have some of those guys."

Five offensive tackles, including Iowa's Tristan Wirfs and USC's Austin Jackson, are listed among the top 27 prospects in Jeremiah's draft rankings. Wirfs and Jackson have the big-man athleticism coveted by a Vikings offense that could either replace its left tackle and/or left guard this offseason.

Vikings coaches and scouts spent time with some projected Day 1 and Day 2 tackles this week in Indianapolis, using one of 45 formal interviews with Auburn's Prince Tega Wanogho. The Tigers' left tackle met with the Vikings on Tuesday night, when they inquired about a Jan. 28 knee surgery that has Wanogho awaiting medical clearance.

Depending on roster moves, the Vikings are open to shuffling the offensive line to make it work. The Vikings again will consider moving Reiff, the 31-year-old veteran, to left guard, according to Zimmer. They appear likely to either bench or release guard Pat Elflein. It's also unclear if the Vikings will keep Reiff at his current $10.9 million base salary — none guaranteed — for 2020.

"Last year, the interior was a little stronger [in the draft]," Spielman said. "This year, I think there's some tackles out there. Some of them, as we go and get to know these kids a little bit, may be ready to go right off the bat."