Rosevelt Colvin celebrates a fourth-quarter safety that gave the Pats a 19-17 win over Buffalo in last season’s opener. Ty Warren had sacked QB J.P. Losman in the end zone.

THE PROVIDENCE JOURNAL / Bob Breidenbach

While speculating about which two players Patriots decision-makers Scott Pioli and Bill Belichick will choose with the two first-round picks they have when the NFL Draft begins tomorrow, the pair’s history in New England makes it easy to believe they might trade the 28th pick.

The Patriots are no strangers to draft-weekend deals, and Pioli and Belichick have swapped picks with other teams on numerous occasions, often acquiring more choices for themselves in the process. With no second-round pick this year — it went to Miami, along with a seventh-round selection, for receiver Wes Welker — New England could shop the 28th pick or another club could ask for it.

New England is the only team holding two first-round choices, having gotten the 24th from Seattle in the Deion Branch trade.

Last year, when receiver Chad Jackson didn’t get picked in the first round, New England made a deal with Green Bay that moved it from 52nd to 36th in the second round and enabled it to get Jackson. The move hasn’t panned out just yet because Jackson struggled with injury last year and is currently recovering from a knee injury suffered in the AFC Championship Game.

The Patriots gave the Packers their pick at 52 as well as a third-round choice.

In 2005, Pioli and Belichick made four trades on draft weekend. On the first day, they gave their second-round choice to Baltimore and got back three picks — third- and fifth-rounders that year and a third-round choice in 2006. The ’05 third-round pick was Ellis Hobbs and the ’06 third-rounder was used in the Green Bay trade that year. The fifth-round slot went to Arizona as part of the not-so-successful deal that brought corner Duane Starks to Foxboro.

New England slid a fifth- and sixth-round pick to Detroit on Day Two two years ago for the fourth-round choice that became fullback/tight end Garrett Mills last year.

One day in 2003 brought the Patriots two-thirds of what has arguably become the best defensive line in football.

Though they had the 14th overall pick that year, New England swapped spots with Chicago at 13, giving the Bears a sixth-round choice the next day, as well. Lucky number 13? Texas A&M’s Ty Warren, who enjoyed a career season last year.

Apparently happy to get Warren, New England sent its second spot in the first round that year, number 19, to Baltimore for the Ravens’ second-round slot and their first-round pick in 2004. The Patriots used the second-round choice on Illinois corner Eugene Wilson and the first-round selection on Miami defensive tackle Vince Wilfork, who also blossomed last season. Baltimore spent the pick it got from the Pats on quarterback Kyle Boller.

Also in ’03, the Patriots dealt with rival Miami, making something of a lopsided deal value-wise that worked out in their favor. The Dolphins got the Pats’ third-round choice in 2003, but New England got Miami’s second-round pick in 2004. Though his time here came to an abrupt end last month, New England sent the second-rounder to Cincinnati for Corey Dillon.

In all, Pioli and Belichick have made 18 trades on or just before draft weekend. Some of the late-round swaps they’ve made have worked out well: the choices that became Dan Koppen, Ryan O’Callaghan and Asante Samuel all came via trade; while others — Kliff Kingsbury, Kenyatta Jones and Rohan Davey — haven’t. But that’s the chance every team takes in the draft.

So don’t be surprised if blogs are buzzing with the news of a Patriots trade tomorrow afternoon, with New England getting two or three picks for its second first-rounder.

Or the Pats could package the 24th and 28th selections and move up. Trying to predict what the Pats might do is close to impossible, but it is at least entertaining to try to figure it out.

smanza@projo.com