Dion Lewis has been a nice piece of the Patriots offense since being acquired in 2015.But now the running back, 27, is expected to become an unrestricted free agent, and there's speculation the 49ers might be a very attractive landing spot.Lewis isn't an NFL star. He hasn't ever rushed for 1,000 yards and isn't mentioned in any discussions about the league's best running backs. Yet Lewis, a quick and tough 5-foot-8, 195-pounder appears to be a good match with the Niners.He's played with quarterback Jimmy Garoppolo in New England, and so would be familiar to the team's new offensive leader. And, he's a versatile back who can be extremely productive as a No. 2 behind Carlos Hyde (if he remains) or another No. 1 running back acquired this offseason.Despite his size, Lewis is known as a fine pass blocker and is an excellent receiver. Over the past three seasons, Lewis has had 36, 17 and 32 receptions for five touchdowns. This past season also was a breakout year for Lewis as a rusher, too, gaining 896 yards — by far a career high — for 5.0 yards per carry and six TDs.Mike Florio of NBC's Pro Football Talk reported recently that the 49ers are a team that would likely be...