Entering the 2013 season, with Baltimore and Oakland now established as contenders with young, exciting rosters and confident leadership, we know it won’t be a surprise to see the Orioles and A’s back in the pennant mix come September. So where should we look to find the most improvement? Three clubs come to mind.

The Blue Jays are rightfully receiving a lot of ink after a busy offseason that drastically upgraded the team’s pitching depth, but they face four strong contenders for the American League East crown in the Rays, Orioles, Red Sox and Yankees.

The Cardinals named Shelby Miller their fifth starter Monday after the right-hander turned in a solid outing in a 4-3 win against the Twins.

Shortstop Xander Bogaerts, who many consider to be the top prospect in the Red Sox’s farm system, was reassigned to Minor League camp following Monday’s 12-9 loss to the Orioles.

Jackie Bradley Jr. sat around for the first six innings of Monday’s game, but the idle time did not cool off his bat. The prospect, who is still strongly in the mix to land a roster spot for Opening Day, aided his cause yet again, delivering a pinch-hit, two-run single up the middle and banging a triple off the wall in right.

Rangers closer Joe Nathan pitched an inning in a Minor League camp on Monday. The outing came after Nathan pitched a scoreless inning against the Reds on Sunday, striking out two of the three batters faced.

Matt den Dekker will not need surgery on his broken right wrist, the outfield prospect tweeted on Monday, in what he called the “best possible news.”

Apparently, Dillon Gee was not exaggerating when he said something “clicked” in his final inning against the Astros last week.

Even amidst a remarkable spring — command-wise, at least — Rick Porcello is finding things to fine-tune. The right-hander has now gone all six outings without walking a batter following Monday’s start in a 6-3 win over the Marlins.

The Indians continued to pare down their roster on Monday, making a wave of moves that brought their Opening Day roster into focus.

The Brewers are a team that can contend in the National League Central, and that statement is a bit easier to believe now that Kyle Lohse is aboard.

Collin Cowgill hit his fourth home run of the Grapefruit League season and Dillon Gee cruised through six scoreless innings as the Mets beat the Braves, 7-4, at Champion Stadium Monday afternoon.

J.P. Arencibia homered twice and drove in five, and Jose Reyes added three RBIs as the Blue Jays roughed up left-hander John Lannan in a 13-4 win over the Phillies on Monday afternoon at Florida Auto Exchange Stadium.

Cubs pitcher Scott Baker was relieved to find out there was nothing structurally wrong with his right elbow, and all he needs to do is rest and let the muscle strain heal.

Red Sox center fielder Jacoby Ellsbury was predictably sore Monday, a day after leaving the game with a jammed right heel. However, this injury is not expected to linger and manager John Farrell expressed hope that Ellsbury will be right back in the leadoff spot on Wednesday against the Marlins.

Kyle Lohse agreed to a three-year, $33 million deal with the Brewers on Monday, pending a physcial. The right-hander turned down a $13.3 million qualifying offer from the Cardinals in November.

As much as Lyle Overbay tried to downplay it, Monday was more than just another day for him in the grind of Spring Training. Not only did he make the start at first base against the Orioles, but it was likely his final appearance before the Red Sox decide his fate.